tag:theconversation.com,2011:/au/topics/elements-2019-67438/articlesElements 2019 – The Conversation2019-12-26T21:40:07Ztag:theconversation.com,2011:article/1177512019-12-26T21:40:07Z2019-12-26T21:40:07ZThat’s a relief! We have a way to recover phosphorus from our urine<figure><img src="https://images.theconversation.com/files/301910/original/file-20191115-47161-1cnaml8.jpg?ixlib=rb-1.1.0&rect=49%2C917%2C5472%2C2703&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Phosphorus was first discovered by boiling down thousands of litres of urine.</span> <span class="attribution"><span class="source">Shutterstock/Lesterman</span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at some of the elements used by researchers in their work.</em></p>
<p><em>Today’s focus is phosphorus, an element that is vital for life but of limited supply. But we can recover phosphorus from a source that we all give away freely, every day, our urine.</em></p>
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<p><a href="http://www.rsc.org/periodic-table/element/15/phosphorus">Phosphorus</a>, number 15 on the periodic table, can be highly toxic and flammable and has been used in warfare as an <a href="https://www.reuters.com/article/us-afghanistan-phosphorus-facts-sb/factbox-key-facts-about-white-phosphorus-munitions-idUSTRE5471T620090508">incendiary device</a>, yet it is also essential for life.</p>
<p>As the famous science writer Isaac Asimov said in his 1974 book, <a href="https://books.google.com.au/books?id=t5EoAQAAMAAJ">Asimov on Chemistry</a>:</p>
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<p>Life can multiply until all the phosphorus has gone and then there is an inexorable halt which nothing can prevent.</p>
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Read more:
<a href="https://theconversation.com/titanium-is-the-perfect-metal-to-make-replacement-human-body-parts-115361">Titanium is the perfect metal to make replacement human body parts</a>
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<p>That’s because phosphorus is essential to all living organisms. It forms the backbone of our DNA as well as the molecule adenosine triphosphate (<a href="https://www.britannica.com/science/adenosine-triphosphate">ATP</a>) that is found in cells and captures chemical energy from the food we eat.</p>
<p>We have yet to find a single living being that does not require phosphorus to survive. But we don’t have an endless supply of phosphorus, and that’s where my research comes in.</p>
<h2>Demand grows for phosphorus</h2>
<p>Demand for phosphorus and nitrogen increased dramatically in the 20th century as it was found to play a crucial role in fertiliser used for growing crops. </p>
<p>In just over 50 years (between 1961 and 2014) fertiliser production increased <a href="https://ourworldindata.org/fertilizer-and-pesticides">tenfold</a> due to the so-called <a href="https://www.encyclopedia.com/plants-and-animals/agriculture-and-horticulture/agriculture-general/green-revolution">green revolution</a>.</p>
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<span class="caption">Phosphorus is an important ingredient in many fertilisers used to help grow our plant based foods.</span>
<span class="attribution"><span class="source">Shutterstock/otick</span></span>
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<p>This allowed for a worldwide increase in the agricultural production, particularly in the developing world, which was used to feed an ever-growing global population. </p>
<p>The high demand for nitrogen was met by ramping up a <a href="https://www.britannica.com/technology/Haber-Bosch-process">process</a> that captures nitrogen and hydrogen from fresh air and uses it to synthesise ammonia (the major nitrogen-based fertiliser). As the air in Earth’s atmosphere is made of <a href="https://climate.nasa.gov/news/2491/10-interesting-things-about-air/">78% nitrogen</a>, synthetic ammonia production was only limited by its cost. </p>
<p>But phosphorus is generally stored in solid or liquid form, and the cheapest way to cope with the high demand for phosphorus fertiliser was to extract if from phosphate rocks.</p>
<p>Phosphate rocks are a resource that is both limited and not equally distributed. The <a href="https://www.usgs.gov/centers/nmic/phosphate-rock-statistics-and-information">top five phosphate rocks holders</a> – Morocco and Western Sahara, China, Algeria, Syria, and Brazil – account for 84% of the world reserves. Australia holds just 1.6%.</p>
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<p>As phosphate rocks are a finite and non-renewable resource, the continuous extraction is causing <a href="https://www.sciencedirect.com/science/article/pii/S0959378015300765" title="A half-century of global phosphorus flows, stocks, production, consumption, recycling, and environmental impacts">uncertainties in our future supplies</a>.</p>
<h2>The wee supplies of phosphorus</h2>
<p>One solution is to look for other supplies of phosphorus, and that’s where you and I can play a role. Our urine is an excellent source of raw material for phosphorus. </p>
<p>Each one of us excretes up to <a href="https://www.sciencedirect.com/science/article/pii/S221334371830188X" title="Urine: The liquid gold of wastewater">half a kilogram</a> of phosphorus per year, just through our urine. This makes urine the <a href="https://www.sciencedirect.com/science/article/pii/S0045653511001925" title="Global potential of phosphorus recovery from human urine and feces">single largest</a> source of phosphorus from urban areas.</p>
<p>Back in the 17th century, the German chemist <a href="https://www.sciencehistory.org/distillations/hennig-brandt-and-the-discovery-of-phosphorus">Hennig Brandt</a> chose urine to isolate elemental phosphorus. In his experiment, he boiled hundreds of litres of urine down to a thick syrup until a red oil distilled up from it.</p>
<p>He collected the oil and cooled down the urine. After discarding the salts formed at the bottom of the mixture, he added back the red oil. By heating back the mixture for 16 hours, a white fume would come out, then oil, and finally <a href="https://www.sciencedirect.com/science/article/pii/S0045653511002499" title="A brief history of phosphorus: From the philosopher’s stone to nutrient recovery and reuse">phosphorus</a>.</p>
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<p>He was actually searching for the legendary <a href="https://www.sciencedirect.com/science/article/pii/S0045653511002499">Philosopher’s Stone</a> that would supposedly turn any metal into gold. He might have failed in that, but he showed how easy it was to isolate phosphorus from urine with unsophisticated tools.</p>
<h2>Reduce, reuse, recycle</h2>
<p>Today’s approaches to recycling of phosphorus from our wastes are way more practical and economical compared to Brandt’s method.</p>
<p>An increasing number of <a href="https://ostara.com/nutrient-management-solutions/">companies</a> are looking to <a href="https://www.suezwaterhandbook.com/degremont-R-technologies/sludge-treatment/recovery/recycle-phosphorus-from-effluent-to-produce-a-valuable-fertilizer-Phosphogreen">recover phosphorus</a> from waste water, including from <a href="https://www.sciencedirect.com/science/article/pii/S0043135410007025" title="Low-cost struvite production using source-separated urine in Nepal">urine</a>.</p>
<p>New <a href="http://www.vuna.ch/aurin/index_en.html">urine-derived fertilisers</a> have entered the market and the race is on to find the optimal technology to convert smelly urine into a safe, non-odorous commercial fertiliser. </p>
<p>In Australia, researchers from the University of Technology Sydney have developed a process that uses urine as a raw material to produce fertiliser and freshwater. Selected microorganisms are used to oxidise the (smelly) compounds in raw urine and convert volatile ammonia into more stable nitrates.</p>
<p>The treated urine is then filtered through a membrane, which retains the microorganisms allowing for their re-use, while allowing the soluble phosphorus and nitrogen to pass through. Treated and filtered urine is concentrated to reach nutrients concentration similar to commercial fertilisers. </p>
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<em>
<strong>
Read more:
<a href="https://theconversation.com/silver-makes-beautiful-bling-but-its-also-good-for-keeping-the-bacterial-bugs-away-115367">Silver makes beautiful bling but it's also good for keeping the bacterial bugs away</a>
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<p>At present, this fertiliser – named UrVal short for “You are Valuable” – is being tested at the Royal Botanical Garden in growing parsley.</p>
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<a href="https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/303056/original/file-20191122-112990-1ufdexv.JPG?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Parsley grown using UrVal fertiliser at the Sydney Royal Botanical Garden.</span>
<span class="attribution"><span class="source">Dr. Ibrahim El Saliby</span>, <span class="license">Author provided</span></span>
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<p>Clearly, these new innovations in nutrients recovery from wastes allow us to reduce the dependence on a finite resource (phosphorus).</p>
<p>But they could also enable us to explore the possibility of one day producing food outside of planet Earth where we need fertiliser. Phosphate rocks may not be available in such places, but we’d have plenty of urine.</p><img src="https://counter.theconversation.com/content/117751/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Federico Volpin does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>We need phosphorus for life, as well as for fertiliser to help plants grow, but raw supplies are limited.Federico Volpin, PhD Fellow, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1179062019-07-17T19:49:37Z2019-07-17T19:49:37ZWhen an artist looks at a chemical element, what do they see?<figure><img src="https://images.theconversation.com/files/283811/original/file-20190712-173342-ypail1.jpg?ixlib=rb-1.1.0&rect=231%2C28%2C2728%2C1498&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Artists Damon Kowarsky and Hyunju Kim produced a series of 51 artistic interpretations of elements from the Periodic Table.
</span> <span class="attribution"><span class="license">Author provided</span></span></figcaption></figure><p>Artistic depictions of several chemical elements feature in a new exhibition from today as part of Australia’s celebrations for the <a href="https://www.iypt2019.org/">International Year of the Periodic Table</a>.</p>
<p>They are the work of artists <a href="http://damon.tk/">Damon Kowarsky</a> and Hyunju Kim, who worked together since December 2018 on the renditions that will be on display at <a href="https://www.quantumvictoria.vic.edu.au/">Quantum Victoria</a>, a specialist science and mathematics centre in the northern suburbs of Melbourne.</p>
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<span class="caption">Damon Kowarsky and Hyunju Kim.</span>
<span class="attribution"><span class="source">Photo credit Delilah Yu</span></span>
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<p>The project followed a chance meeting between Damon and Soula Bennett, the director of Quantum Victoria. Soula believes Science, Technology, Engineering and Mathematics (STEM) naturally extend to incorporate art.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-periodic-table-from-its-classic-design-to-use-in-popular-culture-52822">The periodic table: from its classic design to use in popular culture</a>
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<p>So Damon and Kim were commissioned to produce a series of 51 artistic interpretations illustrating elements of significance in the story of the birth of the universe from the Periodic Table.</p>
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<span class="caption">Mat Greentree and Damon Kowarsky installing some of the works at Quantum.</span>
<span class="attribution"><span class="source">Photo credit Hyunju Kim</span></span>
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<p>While Kowarsky was responsible for creating the drawings of the panels, the colours are by Kim.</p>
<p>As scientists who work with many elements from a scientific point of view, we were curious as to how Kowarsky chose some of the representations he did, so we asked him to describe the artistic process for some of his favourite elements. </p>
<h2>Helium (<a href="http://www.rsc.org/periodic-table/element/2/helium">He</a>)</h2>
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<a href="https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279644/original/file-20190616-158958-13i914n.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The helium (He) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
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<p><strong>Popular view:</strong> Used for balloons and to make your voice sound funny as it’s lighter and less dense than air.</p>
<p><strong>Chemist’s view:</strong> An unreactive (noble) gas that is particularly useful in cooling applications – liquid helium at -269°C is used to keep magnets at a superconducting temperature. Element with the lowest boiling point.</p>
<p><strong>Artist’s view (Damon):</strong> Helium is colourless, odourless, tasteless, almost completely inert, not commonly found on Earth, and named after the Sun, whose image dominated the design I completed for hydrogen.</p>
<p>Not a promising start in terms of visualisation! </p>
<p>In many ways it’s the most abstract of elements, and this ultimately was the clue that unlocked the design. The background composition is structured around a chart showing the passage of the Sun through the sky at the latitude and longitude of <a href="https://www.charleslatrobecollege.vic.edu.au/">Charles La Trobe College</a> (in Melbourne, the site of the installation) on January 1.</p>
<p>Overlaid onto this is the sequence of helium formation in stellar nucleosynthesis, a graph showing the rates of production and consumption of helium (despite its prevalence in the universe it’s a finite resource on Earth) and the bars of the absorption spectrum that allowed this, the first ever extraterrestrial element, to be discovered.</p>
<h2>Iron (<a href="http://www.rsc.org/periodic-table/element/26/iron">Fe</a>)</h2>
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<span class="caption">The iron (Fe) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
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<p><strong>Popular view:</strong> Used to make steel. Iron ore is the source of much of Australia’s wealth. Found in blood.</p>
<p><strong>Chemist’s view:</strong> The most common element on Earth, making up around 35% of the its mass. Iron is used to catalyse a very important chemical reaction, the combination of nitrogen and hydrogen into ammonia, an essential component of fertiliser. </p>
<p><strong>Artist’s view:</strong> Iron is a pivotal element in the Periodic Table in terms of how the elements are created.</p>
<p>Showing a cross section of Earth allowed me to talk about its prevalence, maintain design coherence through the repetition of circles, and introduce bold and saturated colours. The smaller circle represents a red blood cell (iron is found in haemoglobin) and the pie charts show the relative distribution of iron isotopes.</p>
<p>In the bottom left corner the alchemical symbol for iron (Mars, the masculine attribute) breaks into the form of Earth. Alchemy is important as one of the foundations of modern chemistry and its symbols are historically and visually interesting. I didn’t want it to dominate though, so using a negative shape seemed a good way to balance all these concerns.</p>
<h2>Copper (<a href="http://www.rsc.org/periodic-table/element/29/copper">Cu</a>)</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279646/original/file-20190616-158917-1n030ed.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The copper (Cu) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> For the older generation, copper pipes and <a href="https://www.ramint.gov.au/one-cent">1</a> and <a href="https://www.ramint.gov.au/two-cents">2</a> cent coins.</p>
<p><strong>Chemist’s view:</strong> Metal with very high thermal and electrical conductivity. Very useful for catalysing some chemical reactions, especially a so-called click reaction where two molecules can be quickly linked together under mild conditions.</p>
<p><strong>Artist’s view:</strong> With copper there’s the amazing colour and its history as one of the oldest metals known to humans.</p>
<p>I relied on the element’s utility and familiarity, and wanted to step away from symmetry and the geometric prevalence of circles. Even though copper is inorganic, its malleability and ductility lends an almost lifelike quality to its forms.</p>
<p>A map of Cyprus (copper is named for the place it was first discovered and mined) contributes to the overall balanced asymmetry of the design.</p>
<h2>Calcium (<a href="http://www.rsc.org/periodic-table/element/20/calcium">Ca</a>)</h2>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279648/original/file-20190616-158936-k0xh3i.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The calcium (Ca) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> Found in limestone, chalk and coral, and bones and teeth. </p>
<p><strong>Chemist’s view:</strong> Highly reactive and the most abundant metal in the human body. As calcium chloride, used as a desiccant to remove water from air and solvents so reactions can be done anhydrously (without the presence of water, which can interfere with some reactions).</p>
<p><strong>Artist’s view:</strong> Calcium is common in bones, shells and teeth. The challenge was finding images that were visually interesting and fitted the hexagonal shape.</p>
<p>Happily, this collection of human bones found on the web was neither articulated nor hopelessly jumbled. I was pleased how the curved bones (rib and collar) echo other design elements.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/283440/original/file-20190710-44441-10ytit5.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The energy artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p>Shells of course follow the Fibonacci Curve, whose elegant spiral can be seen in the another panel of the exhibit (“Energy”), where it represents a timeline of the universe.</p>
<h2>Nitrogen (<a href="http://www.rsc.org/periodic-table/element/7/nitrogen">N</a>)</h2>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/279650/original/file-20190616-158953-9w19e6.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The nitrogen (N) artwork.</span>
<span class="attribution"><span class="source">Damon Kowarsky and Hyunju Kim</span></span>
</figcaption>
</figure>
<p><strong>Popular view:</strong> Forms about 78% of Earth’s atmosphere, found in proteins and nucleic acids (DNA, RNA), and a key component of fertilisers.</p>
<p><strong>Chemist’s view:</strong> The triple bond (N≡N) form of nitrogen found in the atmosphere, is the second strongest bond in any diatomic molecule (composed of two elements). Although problematic for chemistry, it is useful as it releases large amounts of energy when broken. This is used both for fertilisers and explosives, and remains an essential process in the chemical industry.</p>
<p><strong>Artist’s view:</strong> Nitrogen compounds are essential for life. There are two main ways atmospheric nitrogen is converted to forms that are usable by plants and animals.</p>
<p>The first is lightning.</p>
<p>The second, and much less dramatic, is the symbiotic relationship between bacteria and the roots of certain plants. Typically these are beans and legumes but Australian wattles and acacias also contain nitrogen-fixing nodules. </p>
<h2>Other artistic elements</h2>
<p>Of course, Damon Kowarsky and Hyunju Kim are not the first to take an artistic look at the elements.</p>
<p>Other examples include a <a href="https://www.bowdoin.edu/news/2019/02/a-first-years-extraordinary-periodic-table.html">graphic artist’s version by Julie Hu</a> to convey to non-scientists the richness of what these substances bring to our world.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/silver-makes-beautiful-bling-but-its-also-good-for-keeping-the-bacterial-bugs-away-115367">Silver makes beautiful bling but it's also good for keeping the bacterial bugs away</a>
</strong>
</em>
</p>
<hr>
<p>Another is a <a href="https://www.sciencehistory.org/distillations/magazine/the-periodic-table-printmaking-project">periodic table printmaking project by Jennifer Schmitt</a>, the daughter of a chemistry teacher mother and an artistic father, she grew up seeing beauty in science.</p>
<p>There is also a <a href="http://www.instantshift.com/2015/09/02/periodic-table-elements-character-design/">depiction of the elements as characters by Kaycie Dunlap</a>, who was inspired by a desire make science more interesting by imagining what the elements would look like in our regular life.</p>
<p>Multiple quilting projects have drawn inspiration from sources such as the elements’ names, unique characteristics, and purposes (<a href="https://hyperallergic.com/236928/quirky-quilts-inspired-by-the-periodic-table/">curated by artist Jill Rumoshosky Werner in 2015</a>) or the wonderful stories about people, cultures, history, art, politics and science associated with them (<a href="https://periodictableinfabric.com/about-the-project/">curated by Kim Baird</a>).</p>
<hr>
<p><em>The artworks are on display from July 18, 2019, at Quantum Victoria, 235 Kingsbury Drive, Macleod, Victoria (they’re also <a href="http://art.damon.fastmail.net/project/science/periodictable/perindex.htm">available online</a>).</em></p>
<p><em>If you’d like to see them please call (03) 9223 1460 or email at <a href="mailto:admin@quantumvictoria.vic.edu.au">admin@quantumvictoria.vic.edu.au</a> to arrange a visit, as this is a school site (co-located with Charles La Trobe P-12 College).</em></p><img src="https://counter.theconversation.com/content/117906/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Blaskovich is a member of the Royal Australian Chemical Institute (RACI) and the American Chemical Society.</span></em></p><p class="fine-print"><em><span>Frances Separovic receives funding from Australian Research Council (ARC) and National Health & Medical Research Council (NHMRC). She is a member of the American Chemical Society, ANZMAG, Biophysical Society, ISMAR and RACI.</span></em></p>From heavy metal to lighter than air gas, these elements and others from the Periodic Table are transformed into artworks that go on display from today.Mark Blaskovich, Senior Research Officer, The University of QueenslandFrances Separovic AO FAA, Professor of Chemistry, The University of MelbourneLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1153672019-06-11T20:12:02Z2019-06-11T20:12:02ZSilver makes beautiful bling but it’s also good for keeping the bacterial bugs away<figure><img src="https://images.theconversation.com/files/278843/original/file-20190611-32321-k3juqs.jpg?ixlib=rb-1.1.0&rect=148%2C107%2C4940%2C3145&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Silver has been used to make jewellery for centuries but it's also good at killing bacteria and could be used in new antibiotics.</span> <span class="attribution"><span class="source">Shutterstock/Santi S</span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at some of the elements used by researchers in their work.</em></p>
<p><em>Today’s focus is silver, an element seen as a marker of second place – but this reputation is undeserved.</em></p>
<hr>
<p><a href="http://www.rsc.org/periodic-table/element/47/silver">Silver</a> has long played second fiddle to other elements. In sport, it is the symbol of second place, giving way to gold in the medals. In jewellery, airline frequent flyer programs and credit cards, silver is also topped by gold and platinum.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/278825/original/file-20190611-32342-jp4knh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Hold that silver high! Proud medal winners from the Sochi Winter Olympics, 2014.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/andymiah/12515487734/">Flickr/Andy Miah</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
</figcaption>
</figure>
<p>But in the world of useful elements, silver should be gold.</p>
<p>My interest in silver originated when growing up in Canada, searching through loose change for pre-1968 quarters (25 cents) that were made from 80% silver (currently worth at least <a href="https://www.ngccoin.com/price-guide/series-detail.aspx?MVDetailID=55&Series=Canada-Silver-Quarter">US$2.24 each</a>).</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/from-the-bronze-age-to-food-cans-heres-how-tin-changed-humanity-114195">From the bronze age to food cans, here's how tin changed humanity</a>
</strong>
</em>
</p>
<hr>
<p>More recently, in my <a href="http://www.aidrc.org.au/mark-blaskovich">current scientific role fighting antimicrobial resistance</a>, my interest has been piqued by silver’s association with killing bacteria.</p>
<h2>The silver medical treatment</h2>
<p>Silver has a <a href="https://www.sciencedirect.com/science/article/pii/S0734975018300946" title="Silver bullets: A new lustre on an old antimicrobial agent">long history of antibacterial activity</a>. The Phoenicians lined clay vessels with silver to preserve liquids (around 1300BCE), the Persians and Greeks used silver containers to store drinking water (around 5000-300BCE) and Americans travelling west during the 1880s added silver coins into water barrels. </p>
<p>More recently, <a href="https://www.sciencedirect.com/science/article/pii/S0305417914003040" title="Silver in medicine: A brief history BC 335 to present">both American and Russian space programs have used ionic silver to purify water</a>, including <a href="https://www.space.news/2016-06-06-nasa-open-to-using-silver-treated-water-in-space-despite-fda-opposition.html">on the International Space Station</a>. </p>
<p>Colloidal silver, a suspension of very small nanoparticles of silver metal, has found widespread use as a popular home remedy for a range of ailments, but is often marketed with <a href="https://www.quackwatch.org/01QuackeryRelatedTopics/PhonyAds/silverad.html">dubious claims</a> and is <a href="https://nccih.nih.gov/health/colloidalsilver">not supported by the scientific community</a>.</p>
<p>Some <a href="https://www.purestcolloids.com/history-silver.php">websites claim</a> the use of silver cutlery and dinnerware by wealthy Europeans in the Middle Ages may have helped favour their survival during the bubonic plague, though evidence supporting this is scant.</p>
<p>On a related note, one version of the <a href="https://www.quora.com/How-did-the-term-Blue-Blood-come-about">origin of the term “blue blood”</a> to describe the wealthy is based on their use of silver dinnerware, with significant silver ion ingestion known to cause <a href="https://www.merriam-webster.com/medical/argyria">argyria</a>, or purple-grey skin.</p>
<p>Despite these nonscientific associations, silver has found widespread acceptance in the medical community for specific applications of its antibacterial properties. </p>
<h2>Silver for burns</h2>
<p>Silver nitrate solutions were found to prevent eye infections in newborns in the 1880s, and were still commonly used for this in the 1970s. Solutions were also used to treat burn injuries, leading to many scientific reports in the 1960s, such as a <a href="https://nyaspubs.onlinelibrary.wiley.com/doi/abs/10.1111/j.1749-6632.1968.tb14745.x" title="THE TREATMENT OF EXTENSIVE THERMAL BURNS WITH 0.5% SILVER NITRATE SOLUTION">1968 study on treating extensive thermal burns with 0.5% silver nitrate solution</a> that describes an apparent reduction in death. </p>
<p>Both 0.5% silver nitrate solution and 1% silver sulfadiazine cream are still used in burn care and are accompanied by new silver-based wound dressings. </p>
<p>The antimicrobial use of silver has crept into consumer products, such as <a href="https://www.elastoplast.com.au/products/wound-care/antibacterial-fabric-plaster">antibacterial bandages</a>, <a href="http://thefootshop.com.au/products/carnation-footcare-silversock-black.html">socks</a> and <a href="https://www.nivea.com.au/products/nivea-men-silver-protect-roll-on-deodorant-40058083072720031.html">deodorants</a>, and antibacterial coatings on a range of products such as <a href="https://www.samsung.com/in/support/home-appliances/how-does-silver-nano-coating-help/">refrigerators</a>. </p>
<p>While this may sound like a good idea, there are concerns that widespread use of silver could cause <a href="https://www.nursingtimes.net/clinical-archive/infection-control/bacterial-resistance-to-silver-based-antibiotics/201749.article">bacteria to become resistant</a>, not only to silver, but also to our important antibiotics.</p>
<p>It’s not known exactly how silver kills bacteria, <a href="https://www.sciencedirect.com/science/article/pii/S1549963415006000" title="Silver nanoparticles: A new view on mechanistic aspects on antimicrobial activity">but it seems to work by multiple mechanisms</a>, including cell membrane damage and free radical generation. </p>
<p>Our work on silver is looking at whether it can help existing antibiotics work more effectively, especially against resistant bacteria. This research, which has been ongoing for more than five years, has identified that there is better synergy between silver and some types of antibiotics than others, but we don’t yet know why. </p>
<p>Eventually, this research could lead to new formulations of antibiotics with better activity, where the actual antibiotic remains the same but it is delivered as a salt with silver, instead of a more common ion like sodium.</p>
<h2>The silver resources</h2>
<p>The actual word silver stems from the Anglo-Saxon name for it, siolfur, while its chemical symbol Ag comes from the Latin name for silver, argentum.</p>
<p>Silver can sometimes be found as nuggets of pure metal, though this form is more rare than gold. Most often it is found combined with other elements in ores such as argentite (with sulfur) or galena (with lead).</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/278823/original/file-20190611-32335-1ggjcxg.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Not so shiny yet, a lump of silver ore.</span>
<span class="attribution"><span class="source">Shutterstock/hecke</span></span>
</figcaption>
</figure>
<p>The ores are mined and the silver generally removed by smelting (heating combined with chemical reactions). It is believed this technique was discovered before 2000BCE.</p>
<p>Historically, the major use of silver has been as coinage and in jewellery. Traditional photography uses silver halides for the photosensitive film, while mirror backings and Christmas ornaments use silver-plated glass.</p>
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Read more:
<a href="https://theconversation.com/titanium-is-the-perfect-metal-to-make-replacement-human-body-parts-115361">Titanium is the perfect metal to make replacement human body parts</a>
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<p>Silver lies in the middle of the <a href="https://www.raci.org.au/periodic-table-on-show">periodic table</a>. It is encircled by other useful and well-known metals such as (clockwise from above) copper, zinc, cadmium, mercury, gold, platinum, palladium and nickel. </p>
<p>I would argue that silver shines brightly above its neighbours – it actually does, as it has the highest reflectivity of any metal – and also is the best at conducting electricity and heat.</p>
<p>So silver really does deserves top of the podium: a gold for silver!</p>
<hr>
<p><em>If you’re an academic researcher working with a particular element from the periodic table and have an interesting story to tell then why not <a href="https://theconversation.com/au/pitches">get in touch</a>.</em></p><img src="https://counter.theconversation.com/content/115367/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Mark Blaskovich has received funding from government and industry to investigate the antimicrobial activity of silver in combination with other compounds.</span></em></p>For too long silver has been used to mark second best but this element deserves more recognition thanks to its antibacterial properties.Mark Blaskovich, Senior Research Officer, The University of QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1153612019-05-26T19:31:16Z2019-05-26T19:31:16ZTitanium is the perfect metal to make replacement human body parts<figure><img src="https://images.theconversation.com/files/275791/original/file-20190521-23835-38tcg8.jpg?ixlib=rb-1.1.0&rect=0%2C409%2C3149%2C1765&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Titanium is used in knee and hip replacements.</span> <span class="attribution"><span class="source">Monstar Studio/Shutterstock</span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at how researchers study some of the elements in their work.</em></p>
<p><em>Today’s it’s titanium, a metal known for its strength and lightness so it’s ideal for making replacement hips, knees and other parts of our bodies, but it’s also used in other industries.</em></p>
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<p><a href="http://www.rsc.org/periodic-table/element/22/titanium">Titanium</a> gets its name from the <a href="https://www.britannica.com/topic/Titan-Greek-mythology">Titans of ancient Greek mythology</a> but this thoroughly modern material is well suited to a huge range of high-tech applications.</p>
<p>With the chemical symbol Ti and an atomic number of 22, titanium is a silver-coloured metal valued for its low density, high strength, and resistance to corrosion.</p>
<p>I first studied titanium via a Master’s degree at the Institute of Metal Research in the Chinese Academy of Sciences in 1999. One of my projects was to investigate the formation of titanium alloys for their high-strength characteristics.</p>
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Read more:
<a href="https://theconversation.com/from-the-bronze-age-to-food-cans-heres-how-tin-changed-humanity-114195">From the bronze age to food cans, here's how tin changed humanity</a>
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<p>Since then, the applications for this metal have grown exponentially, from its use (as <a href="https://www.britannica.com/science/titanium-dioxide">titanium dioxide</a>) in paints, paper, toothpaste, sunscreen and cosmetics, through to its <a href="https://www.britannica.com/science/titanium">use as an alloy</a> in biomedical implants and aerospace innovations.</p>
<p>Particularly exciting is the perfect marriage between titanium and 3D printing.</p>
<h2>Custom design from 3D printing</h2>
<p>Titanium materials are expensive and can be problematic when it comes to traditional processing technologies. For example, its high melting point (1,670°C, much higher than <a href="https://www.bssa.org.uk/topics.php?article=103">steel alloys</a>) is a challenge.</p>
<p>The relatively low-cost precision of 3D printing is therefore a game-changer for titanium. 3D printing is where an object is built layer by layer and designers can create amazing shapes.</p>
<p>This allows the production of complex shapes such as replacement parts of a <a href="https://www.abc.net.au/news/2017-03-30/victorian-woman-gets-3d-printed-jawbone-implant/8400410">jaw bone</a>, <a href="https://www.abc.net.au/news/2014-10-21/rare-cancer-sufferer-receives-3d-printed-heel/5830432">heel</a>, <a href="https://www.southampton.ac.uk/news/2014/05/16-ground-breaking-hip-and-stem-cell-surgery.page">hip</a>, <a href="https://www.ncbi.nlm.nih.gov/pubmed/27313616">dental implants</a>, or <a href="http://www.media-studio.co.uk/news/media-studios-first-3d-printed-titanium-cranioplasty-plate-delivered">cranioplasty plates</a> in surgery. It can also be used to make <a href="https://3dprint.com/219546/3d-print-golf-clubs-and-equipment/">golf clubs</a> and <a href="https://www.reuters.com/article/us-norsk-boeing-idUSKBN17C264">aircraft components</a>.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/8Np_NVNx2UI?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Even beer containers benefit from 3D printing with titanium.</span></figcaption>
</figure>
<p>The <a href="https://www.csiro.au/en/Research/MF/Areas/Metals/Lab22">CSIRO is working with industry</a> to develop new technologies in 3D printing using titanium. (It even <a href="https://www.youtube.com/watch?v=8oc8GoOOUo4">made a dragon</a> out of titanium.) </p>
<p>Advances in 3D printing are opening up new avenues to further improve the function of <a href="https://www.materialise.com/pl/node/3197">customised bodypart implants</a> <a href="https://www.renishaw.com/en/metal-3d-printing-for-healthcare--24226">made of titanium</a>.</p>
<p>Such implants can be designed to be porous, making them lighter but allowing blood, nutrients and nerves to pass through and can even <a href="https://3dprint.com/219795/3d-printed-lattice-structures/">promote bone in-growth</a>.</p>
<h2>Safe in the body</h2>
<p>Titanium is considered the most biocompatible metal – not harmful or toxic to living tissue – due to its resistance to corrosion from bodily fluids. This ability to withstand the harsh bodily environment is a result of the protective oxide film that forms naturally in the presence of oxygen.</p>
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<strong>
Read more:
<a href="https://theconversation.com/hydrogen-fuels-rockets-but-what-about-power-for-daily-life-were-getting-closer-112958">Hydrogen fuels rockets, but what about power for daily life? We're getting closer</a>
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<p>Its ability to physically bond with bone also gives titanium an advantage over other materials that require the use of an adhesive to remain attached. Titanium implants last longer, and much larger forces are required to break the bonds that join them to the body compared with their alternatives.</p>
<p>Titanium alloys commonly used in load-bearing implants are significantly less stiff – and closer in performance to human bone – than stainless steel or cobalt-based alloys.</p>
<h2>Aerospace applications</h2>
<p>Titanium weighs about half as much as steel but is 30% stronger, which makes it ideally suited to the aerospace industry where every gram matters.</p>
<p>In the late 1940s the US government helped to get production of titanium going as it could see its potential for “<a href="https://titaniumprocessingcenter.com/titanium-technical-data/titanium-history-developments-and-applications/">aircraft, missiles, spacecraft, and other military purposes</a>”.</p>
<p>Titanium has increasingly become the buy-to-fly material for aircraft designers striving to develop faster, lighter and more efficient aircraft.</p>
<p>About 39% of the US Air Force’s <a href="https://www.airforce-technology.com/projects/f22/">F22 Raptor</a>, one of the most advanced fighter aircraft in the world, is made of titanium.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=600&fit=crop&dpr=1 600w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=600&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=600&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=754&fit=crop&dpr=1 754w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=754&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/275806/original/file-20190522-187172-ptx8lk.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=754&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A titanium 3D printed part (bottom) alongside the aluminum part (top) it will replace on an F-22 Raptor: the titanium part will not corrode, can be procured faster, and costs less.</span>
<span class="attribution"><a class="source" href="https://www.afrc.af.mil/News/Article/1734558/first-metallic-3d-printed-part-installed-on-f-22/">US Air Force photo by R. Nial Bradshaw</a></span>
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<p>Civil aviation moved in the same direction with Boeing’s new <a href="https://www.sciencedirect.com/topics/engineering/boeing-787-dreamliner">787 Dreamliner made of 15% titanium</a>, significantly more than previous models.</p>
<p>Two key areas where titanium is used in airliners is in their landing gear and jet engines. Landing gear needs to withstand the massive amounts of force exerted on it every time a plane hits a runway.</p>
<p>Titanium’s toughness means it can absorb the huge amounts of energy expelled when a plane lands without ever weakening.</p>
<p>Titanium’s heat resistance means it can be used inside modern jet engines, where temperatures can reach 800°C. Steel begins to soften at around 400°C but titanium can withstand the intense heat of a jet engine without losing its strength.</p>
<h2>Where to find titanium</h2>
<p>In its natural state, titanium is always found bonded with other elements, usually within igneous rocks and sediments derived from them.</p>
<p>The most commonly mined materials containing titanium are <a href="https://geology.com/minerals/ilmenite.shtml">ilmenite</a> (an iron-titanium oxide, FeTiO<sub>3</sub>) and <a href="https://geology.com/minerals/rutile.shtml">rutile</a> (a titanium oxide, TiO<sub>2</sub>).</p>
<p>Ilmenite is most abundant in China, whereas Australia has the highest global proportion of rutile, <a href="http://www.ga.gov.au/education/classroom-resources/minerals-energy/australian-mineral-facts/titanium#heading-6">about 40% according to Geoscience Australia</a>. It’s found mostly on the east, west and southern coastlines of Australia.</p>
<p>Both materials are generally extracted from sands, after which the titanium is separated from the other minerals.</p>
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<strong>
Read more:
<a href="https://theconversation.com/where-did-you-grow-up-how-strontium-in-your-teeth-can-help-answer-that-question-112705">Where did you grow up? How strontium in your teeth can help answer that question</a>
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<p>Australia is one of the world’s <a href="https://minerals.usgs.gov/minerals/pubs/commodity/titanium/mcs-2015-timin.pdf">leading producers of titanium</a>, producing more than 1.5 million tonnes in 2014. South Africa and China are the two next leading producers of titanium, producing 1.16 and 1 million tonnes, respectively.</p>
<p>Being among the top ten most abundant elements in Earth’s crust, titanium resources aren’t currently under threat – good news for the many scientists and innovators constantly looking for new ways to improve life with titanium.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/8oc8GoOOUo4?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How to make a dragon using titanium!</span></figcaption>
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<p><em>If you’re an academic researcher working with a particular element from the periodic table and have an interesting story to tell then why not <a href="https://theconversation.com/au/pitches">get in touch</a>.</em></p><img src="https://counter.theconversation.com/content/115361/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Laichang Zhang receives funding from Australian Research Council through Discovery Projects. </span></em></p>Titanium is a tough but light metal that makes great replacements for bone in our body. But it has plenty of other uses in industry as well.Laichang Zhang, Professor Mechanical Engineering, Edith Cowan UniversityLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1141952019-03-28T18:09:26Z2019-03-28T18:09:26ZFrom the bronze age to food cans, here’s how tin changed humanity<figure><img src="https://images.theconversation.com/files/266240/original/file-20190328-139341-e5mo6b.jpg?ixlib=rb-1.1.0&rect=0%2C475%2C4288%2C2355&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Tin comes from the ore cassiterite.</span> <span class="attribution"><span class="source">Shutterstock/PYP </span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at how researchers study some of the elements in their work.</em></p>
<p><em>Today’s it’s tin, a chemical that has little use by itself, but mix it with other elements and it takes on a whole new life.</em></p>
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<p>Mention tin and most people would think of the typical tin can, used to preserve foods you store in your cupboards. Tin is used here to help protect the can against corrosion (although <a href="https://www.ucan-packaging.com/blog/what-are-tin-cans-made-of/">not all cans</a> today contain tin).</p>
<p>But while the use of tin in canning only <a href="http://www.cancentral.com/content/nicolas-appert-father-canning">dates back to the early 1800s</a>, the mixing of tin with other elements dates back many centuries.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=393&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=393&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=393&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=493&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=493&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266239/original/file-20190328-139374-v9hxsy.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=493&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">The tin in cans helps to protect them from corrosion.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/tsausawest/8508069576/">Flickr/Salvation Army USA West</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Tin – <a href="http://www.rsc.org/periodic-table/element/50/tin">chemical symbol Sn</a> with an atomic number 50 on the periodic table – is soft and silvery in colour, with a melting point of only 232°C. At first sight it doesn’t seem to be a promising prospect for making anything. </p>
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<strong>
Read more:
<a href="https://theconversation.com/where-did-you-grow-up-how-strontium-in-your-teeth-can-help-answer-that-question-112705">Where did you grow up? How strontium in your teeth can help answer that question</a>
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<p>Somehow, humans discovered that adding controlled amounts of tin to copper produced a splendid, golden-yellow alloy we call bronze.</p>
<p>I first became interested in bronze during my final year undergraduate research project in 1978. That interest continues today – I’m working with colleagues in Thailand to reverse-engineer the technologies used to make ancient Thai bronze bangles. </p>
<h2>Early bronze</h2>
<p>The first known tin bronzes seem to have appeared in the Caucasus region of Eurasia in about 5800 to 4600 BCE. That these very scarce early examples of tin bronze may have been accidentally made from rather rare ores that naturally contained both copper and tin simultaneously.</p>
<p>There is abundant evidence that by about 3000 BCE, tin bronzes were being made in the Aegean and Middle East (Turkey, Syria, Iraq, Iran) by deliberately alloying tin and copper, with the ores being obtained from separate sources.</p>
<p>Clearly, a series of somewhat unlikely events had to occur before this could be the norm.</p>
<p>An accidental melt would have to have been made from suitable minerals containing oxides of tin and copper. The resulting metal would have to be recognised to have desirable properties, such as hardness, colour and toughness, such that superior weapons or ornaments could be produced.</p>
<p>Craftspeople would then have had to be organised enough to be able to work out how to repeat this smelting process to create artefacts such as swords, axe heads, bowls and bangles.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=392&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=392&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=392&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=492&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=492&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266262/original/file-20190328-139374-1o61wq4.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=492&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">This 4000-year-old bronze axe with a low tin content was found in Sweden.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/historiska/4655950292/">Flickr/The Swedish History Museum</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Trading networks then had to be established to bring the comparatively rare tin from faraway places, such as Afghanistan or Cornwall in Britain’s southwest, to any foundry. The metallurgical craft would have to be passed on to other practitioners, probably by oral means.</p>
<h2>The spread of bronze</h2>
<p>The trick of deliberately adding tin to copper then spread throughout the Old World, reaching Western Europe by about 2800 BCE, Egypt by 2200 BCE, the populous North China Plain by 2200 BCE, China’s Yunnan province by about 1400 BCE, Thailand by about 1100 BCE, and southern India by 1000 BC (if not a century or two earlier).</p>
<p>This has led to some robust discussion among archaeometallurgists on whether the special knowledge of tin’s useful attributes spread from a single founding location in the Middle East, or whether it had been repeatedly independently developed by indigenous craftspeople.</p>
<p>In the case of Thailand and Cambodia, arguments have been raised for several scenarios: that the technology was independently developed, that it was brought south from China (or maybe the reverse, exported from northeast Thailand to China), or that it was imported from Bengal.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=369&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=369&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=369&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=464&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=464&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266247/original/file-20190328-139352-1e12w6u.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=464&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">An ancient Thai bronze bangle from a site at Sa Kweo in east Thailand.</span>
<span class="attribution"><span class="source">Courtesy of Dr Supitcha Supansomboon and Assoc Prof Seriwat Saminpanya</span>, <span class="license">Author provided</span></span>
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<p>With China, some local scholars have favoured the view for independent local discovery of tin bronze, although it the balance of evidence suggests that the knowledge was transmitted by horseriding visitors from West Asia.</p>
<h2>African bronze</h2>
<p>Tin was also mined in precolonial times in Southern Africa, and some bronze artefacts – such as pieces of metal sheet or ingots – have been recovered at old metalworking sites there.</p>
<p>The available evidence for this region suggests the technology for producing and working iron, copper and bronze appeared contemporaneously at locations in sub-Saharan Africa, beginning about 500 BCE in the north and reaching South Africa in about 300 CE.</p>
<p>How did the metallurgical knowledge get to Southern Africa? Was it an indigenous discovery of the Bantu of East Africa that was then carried with them on their migrations, or was the skill transmitted southwards from the Middle East, and if so by who and how? </p>
<p>As in the case of Asia, interpretation of these issues can be coloured by modern political sensibilities. The question of the source of the metalworking skills that produced the beautiful copper and gold ornaments of the ancient city of Mapungubwe in South Africa, for example, has still not been settled. </p>
<h2>Bronze in the Americas</h2>
<p>The ancient cultures of the Americas also developed sophisticated skills for processing precious metals, copper and tin.</p>
<p>They were able to manufacture bronze artefacts such as rings, pendants, body ornaments, ornamental tweezers, sheet metal breastplates, large discs, ornamental shields and especially bells, by casting, albeit only from about 1000 CE in South America and then soon afterwards in western Mexico.</p>
<p>In the case of Mesoamerica, the knowledge of bronze was believed to have been carried north from Peru and Ecuador to Mexico by maritime traders. </p>
<p>Clearly, the ancient world, both Old and New, was well connected by lengthy trade routes along which ideas (and in many cases tin) flowed.</p>
<h2>The mix of tin</h2>
<p>The transmission of the technology can also be followed by paying attention to specific aspects of the physical metallurgy involved.</p>
<p>When more than about 15% tin by mass is added to the copper, the resulting alloy becomes rather brittle in its cast form, even if it still has a wonderfully warm golden yellow colour.</p>
<p>Somebody, somewhere, made the remarkable discovery that if such a casting is rapidly quenched from red heat into water (or better, brine), it becomes softer and relatively more ductile and workable.</p>
<p>The quenching heat treatment leaves a very characteristic needle-like microstructure (known as martensite) in the artefact that can be detected by a microscope. This tells an archaeologist that the part has been manufactured by a comparatively complex process, rather than merely cast.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266257/original/file-20190328-139364-1tom8p2.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The presence of martensite needles in microsections taken through high-tin bronze artefacts is a sure sign that they have been quenched into water from red heat.</span>
<span class="attribution"><span class="source">Michael Cortie</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>When the tin content is less than about 15%, no martensite forms and nothing remarkable happens on quenching.</p>
<p>The result obtained when heat-treating a high-tin bronze is counterintuitive because, when iron is treated this way, it becomes hard and brittle. The trick to make the bronze tough is so specific that it is most likely this knowledge was transmitted from person to person.</p>
<p>Its transfer across the Old World would have required knowledgeable individuals travelling significant distance to foreign climes. The appearance of these artefacts at far-flung locations across Eurasia and Africa is another sign of ancient globalisation.</p>
<h2>An extra element</h2>
<p>There is one more trick that appears in the ancient bronzes, although this one might have been independently discovered at more than one location.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/hydrogen-fuels-rockets-but-what-about-power-for-daily-life-were-getting-closer-112958">Hydrogen fuels rockets, but what about power for daily life? We're getting closer</a>
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<p>Some time in the Late Bronze Age or Early Iron Age (around 500 BCE), craftspeople began to add lead to their tin bronze castings. This gives the molten metal extra fluidity, allowing it to flow into fine detail in a mould so that castings with fine details and embossed figures can be made.</p>
<p>As an element, lead is not as shiny or attractive as tin; it is much denser and is found in quite different ores such as galena (lead sulfide). The earliest known cast bronzes with significant controlled additions of lead appear to be from China (500 BCE to 200 CE). Once again, it was clearly a deliberate innovation, and once again it spread rapidly all over Eurasia.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=525&fit=crop&dpr=1 600w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=525&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=525&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=659&fit=crop&dpr=1 754w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=659&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/266271/original/file-20190328-139364-1gho715.jpeg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=659&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Another ancient bronze from Thailand (measure is in centimetres).</span>
<span class="attribution"><span class="source">Courtesy of Dr Supitcha Supansomboon and Assoc Prof Seriwat Saminpanya</span>, <span class="license">Author provided</span></span>
</figcaption>
</figure>
<p>As more sites such as the ones in eastern Thailand are excavated, and as the database of alloy compositions and dates increases, it will become possible to cast more light on ancient routes of trade, migration and tech transfer. </p>
<p>The presence and usage of tin at these sites will act as a kind of metallurgical DNA, an indicator for ancient cultural and human exchanges.</p>
<hr>
<p><em>If you’re an academic researcher working with a particular element from the periodic table and have an interesting story to tell then why not <a href="https://theconversation.com/au/pitches">get in touch</a>.</em></p><img src="https://counter.theconversation.com/content/114195/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Michael Cortie receives funding from the Australian Research Council.</span></em></p>On its own it’s just tin. But mix it with other elements and it turns into a material that helped shape the ancient world.Michael Cortie, Physics Discipline Leader, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1129582019-03-11T04:14:16Z2019-03-11T04:14:16ZHydrogen fuels rockets, but what about power for daily life? We’re getting closer<figure><img src="https://images.theconversation.com/files/262315/original/file-20190306-48450-1q1zozl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">NASA has launched all of its space shuttle missions using hydrogen as fuel. </span> <span class="attribution"><a class="source" href="https://www.nasa.gov/centers/marshall/history/this-week-in-nasa-history-first-crew-rotation-mission-launches-to-international-space.html">NASA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at elements and how they’re used in research and the real world.</em> </p>
<p><em>Hydrogen is the <a href="http://www.rsc.org/periodic-table/element/1/hydrogen">first element</a> on the periodic table. In its pure form hydrogen is a light, colourless gas, but forms a liquid at very low temperatures.</em></p>
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<p>Have you ever watched a <a href="https://www.youtube.com/watch?v=OnoNITE-CLc">space shuttle launch</a>? The fuel used to thrust these enormous structures away from Earth’s gravitational pull is <a href="https://www.nasa.gov/content/space-applications-of-hydrogen-and-fuel-cells">hydrogen</a>.</p>
<p>Hydrogen also holds potential as a source of energy for our daily activities – driving, heating our houses, and maybe more. </p>
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<strong>
Read more:
<a href="https://theconversation.com/lightweight-of-periodic-table-plays-big-role-in-life-on-earth-109329">Lightweight of periodic table plays big role in life on Earth</a>
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<p>This month the federal coalition government <a href="https://www.theguardian.com/australia-news/2019/mar/01/coalition-launches-push-for-hydrogen-power-in-energy-policy-reboot">opened public consultation</a> on a national hydrogen strategy. Labor has also pledged to <a href="https://www.theguardian.com/australia-news/2019/jan/22/labor-promises-to-supercharge-hydrogen-industry-as-green-groups-say-no-role-for-coal">set aside funding</a> to develop clean hydrogen. The COAG Energy Ministers meeting in December 2018 indicated <a href="http://www.coagenergycouncil.gov.au/publications/establishment-hydrogen-working-group-coag-energy-council">strong support for a hydrogen economy</a>. </p>
<p>But is Australia ready to explore this competitive, low-carbon energy alternative for residential, commercial, industrial and transport sectors?</p>
<p>There are two key aspects to assessing our readiness for a hydrogen economy - technological advancement (can we actually do it?) and societal acceptance (will we use it?). </p>
<h2>Is the technology mature enough?</h2>
<p>The hydrogen economy cycle consists of three key steps:</p>
<ul>
<li>hydrogen production</li>
<li>hydrogen storage and delivery</li>
<li>hydrogen consumption – converting the chemical energy of hydrogen into other forms of energy. </li>
</ul>
<h3>Hydrogen production</h3>
<p>For hydrogen to become a major future fuel, water electrolysis is likely the best method of production. In this process, electricity is used to <a href="https://www.youtube.com/watch?v=HZUgfkPo670&t=31s">split water molecules</a> into hydrogen (H₂) and oxygen (O₂).</p>
<p>This technology becomes <a href="https://www.csiro.au/en/Do-business/Futures/Reports/Hydrogen-Roadmap">commercially feasible</a> when electricity is produced at relatively low costs by renewable sources such as <a href="https://www.nature.com/articles/s41560-019-0326-1">solar and wind</a>. Costs may drop further in the near future as the production technology becomes more efficient. </p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/how-hydrogen-power-can-help-us-cut-emissions-boost-exports-and-even-drive-further-between-refills-101967">How hydrogen power can help us cut emissions, boost exports, and even drive further between refills</a>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/HZUgfkPo670?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">How hydrogen is created and used as a power source.</span></figcaption>
</figure>
<h3>Hydrogen storage and delivery</h3>
<p>Effective storage and delivery are vital for the safe and efficient handling of large amounts of hydrogen. </p>
<p>Because it is very light, hydrogen has conventionally been compressed at high pressure, or liquefied and stored at an extremely low temperature of -253°C. Taking these steps requires an extra energy investment, so efficiency drops by up to 40%. But current hydrogen storage and delivery still rests on these two technologies – compression and liquefaction – as they are proven and supported by well-established infrastructure and experience. </p>
<p>Another option being explored (but needing further development) is to combine hydrogen with other elements, and then release it when required for use. </p>
<p>Currently, most hydrogen fuel cell cars use carbon-fibre reinforced tanks to store highly compressed hydrogen gas. The cost of tanks will need to lower to make this option more economic (currently <a href="https://www.osti.gov/servlets/purl/1343975">over a few thousands of US dollars per unit</a>). </p>
<h3>Using hydrogen as a fuel</h3>
<p>There are two main ways to convert the chemical energy in hydrogen into usable energy (electrical energy or heat energy). Both of these approaches produce water as the by-product.</p>
<p>A primitive and straightforward way of using hydrogen is to burn it to generate heat – just like you use natural gas for cooking and heating in your home. </p>
<p>A <a href="https://www.australiangasnetworks.com.au/our-business/about-us/media-releases/australian-first-hydrogen-pilot-plant-to-be-built-in-adelaide">trial planned for South Australia</a> aims to generate hydrogen using renewable electricity, and then inject it into the local gas distribution network. This way of “blending” gases can avoid the cost of building costly delivery infrastructure, but will incur expenditures associated with modifications to existing pipelines. Extensive study and testing of this activity are required. </p>
<p>When used in hydrogen fuel cells, energy is produced when hydrogen reacts with oxygen. This is the technology used by NASA and other operators in space missions, and by car manufacturers in hydrogen fuel cell cars. It’s the most advanced method for hydrogen use at the moment.</p>
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<iframe width="440" height="260" src="https://www.youtube.com/embed/OnoNITE-CLc?wmode=transparent&start=0" frameborder="0" allowfullscreen=""></iframe>
<figcaption><span class="caption">Turn up the sound for this hydrogen-fuelled launch.</span></figcaption>
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<h2>It works, but will we accept it?</h2>
<h3>Safety considerations</h3>
<p>As a fuel, hydrogen has some properties that make it safer to use than the fuels more commonly used today, such as diesel and petrol. </p>
<p>Hydrogen is non-toxic. It is also much lighter than air, allowing for rapid dispersal in case of a leak. This contrasts with the buildup of flammable gases in the case of diesel and petrol leaks, which can cause explosions. </p>
<p>However, hydrogen does burn easily in air, and ignites more readily than gasoline or natural gas. This is why hydrogen cars have such robust carbon fibre tanks – to prevent leakages. </p>
<p>Where hydrogen is used in commercial settings as a fuel, strict regulations and effective measures have been established to prevent and detect leaks, and to vent hydrogen. Household applications of hydrogen fuel would also need to address this issue. </p>
<h3>Impact on the environment</h3>
<p>From an environmental perspective, the ideal cycle in a hydrogen economy involves: </p>
<ul>
<li>hydrogen production through using electrolysis to split water</li>
<li>hydrogen consumption via reacting it with oxygen in a fuel cell, producing water as a byproduct. </li>
</ul>
<p>If the electricity for electrolysis is generated from renewable sources, this whole value chain has minimal environment impact and is sustainable. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/the-science-is-clear-we-have-to-start-creating-our-low-carbon-future-today-104774">The science is clear: we have to start creating our low-carbon future today</a>
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<h2>Moving closer to a hydrogen economy</h2>
<p>Cheap electricity from renewable energy resources is the key in making large-scale hydrogen production via electrolysis a reality in Australia. Internationally it’s already clear – for example, in <a href="https://www.nature.com/articles/s41560-019-0326-1">Germany and Texas</a> – that renewable hydrogen is cost competitive in niche applications, although not yet for industrial-scale supply. </p>
<p>Techniques for storage and delivery need to be improved in terms of cost and efficiency, and manufacturing of hydrogen fuel cells requires advancement. </p>
<p>Hydrogen is a desirable source of energy, since it can be produced in large quantities and stored for a long time without loss of capacity. Because it’s so light, it’s <a href="https://www.csiro.au/en/Do-business/Futures/Reports/Hydrogen-Roadmap">an economical way to transport energy</a> produced by renewables over large distances (including across oceans). </p>
<p>Underpinned by advanced technologies, with strong support by governments, and commitment from many multinational energy and automobile companies, hydrogen fuel links renewable energy with end-users in a clean and sustainable way. </p>
<p>Let’s see if hydrogen takes off.</p><img src="https://counter.theconversation.com/content/112958/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Zhenguo Huang receives funding from Australian Research Council.</span></em></p>Ever watched a space shuttle launch? The fuel used to thrust these huge structures away from Earth’s gravitational pull is hydrogen. Hydrogen could also be used as a household energy source.Zhenguo Huang, Senior lecturer, University of Technology SydneyLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/1127052019-03-06T07:47:49Z2019-03-06T07:47:49ZWhere did you grow up? How strontium in your teeth can help answer that question<figure><img src="https://images.theconversation.com/files/262330/original/file-20190306-48423-zt3rdo.JPG?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Normanton Aboriginal rangers and archaeologists reburying the skeletal remains of Gkuthaarn and Kukatj children back on country.</span> <span class="attribution"><span class="source">Michael Westaway</span>, <span class="license">Author provided</span></span></figcaption></figure><p><em>To mark the <a href="https://www.iypt2019.org/">International Year of the Periodic Table of Chemical Elements</a> we’re taking a look at how researchers use some of the elements in their work.</em></p>
<p><em>Today’s it’s <a href="http://www.rsc.org/periodic-table/element/38/strontium">strontium</a>, a chemical that can help fireworks burn red. It’s also an element that is naturally found in teeth and can be used as way to identify where somebody grew up.</em></p>
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<p>Thousands of skeletal remains of Aboriginal people are kept in museums across Australia, North America and Europe.</p>
<p>Many Aboriginal people refer to these collections as ancestral remains. Although some have now been returned to their descendant communities, many more await return.</p>
<p>The challenge is knowing where to return them.</p>
<p>One estimate is that up to <a href="http://www.oxfordhandbooks.com/view/10.1093/oxfordhb/9780199569069.001.0001/oxfordhb-9780199569069-e-41">25%</a> of Aboriginal remains held in Australian institutions have no details of where they were taken from.</p>
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<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/what-teeth-can-tell-about-the-lives-and-environments-of-ancient-humans-and-neanderthals-104923">What teeth can tell about the lives and environments of ancient humans and Neanderthals</a>
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<p>Our study, published today in the journal <a href="https://doi.org/10.1002/gea.21728" title="A strontium isoscape of north‐east Australia for human provenance and repatriation">GeoArchaeology</a>, aims to tackle the issue of repatriating such remains. </p>
<p>Our work uses the element strontium to determine specifically where somebody grew up. Strontium is an element in all rock and is transferred into body tissues.</p>
<h2>Chemical help with the past</h2>
<p><a href="http://www.rsc.org/periodic-table/element/38/strontium">Strontium</a>, named after Strontian, a small town in western Scotland, is described as a soft, silvery metal that burns in air and reacts with water.</p>
<p>For decades the ratio of two forms of strontium (the isotopes ⁸⁷Sr/⁸⁶Sr) have been measured in archaeological and palaeontological material. These have helped in answering questions that relate to the behaviour of <a href="https://doi.org/10.1016/0883-2927(94)90063-9">past populations</a>. </p>
<p>Perhaps the most famous study involved the 5,000-year-old <a href="http://www.iceman.it/en/the-iceman/">ice man Otzi</a> who was found in the European Alps. <a href="https://www.sciencedirect.com/science/article/pii/S0168583X03004919">Strontium isotopes in Otzi’s teeth</a> helped scientists determine where he was born in northern Italy, which added to our understanding of the mobility of ancient European populations during the <a href="https://study.com/academy/lesson/copper-age-history.html">Chalcolithic period – the Copper Age from about 3500BCE to 2300BCE</a>. </p>
<p>Here in Australia, the strontium technique has had <a href="https://www.nma.gov.au/__data/assets/pdf_file/0006/4695/FriendsMar04-unraveling.pdf">some use in a few cases</a>, but in general is underutilised. </p>
<h2>More than DNA</h2>
<p>In a complementary project focusing on DNA, <a href="http://advances.sciencemag.org/content/4/12/eaau5064">research has shown</a> that genetic material can be used to help locate Aboriginal populations.</p>
<p>But the recovery of ancient DNA from many ancestral remains in Australia continues to prove challenging. Australia’s harsh environmental conditions lead to a poor state of preservation in many remains. This makes the recovery of biological material for DNA analyses difficult and in some cases not at all possible. </p>
<p>Using the isotope chemistry of tooth enamel and bone we can bypass these issues of preservation. The strontium-based process involves measuring a robust geochemical signature, not a biological one subject to decomposition. </p>
<p>Tooth enamel is the hardest substance in the human body and can hold evidence of the region where a person lived as a child. This makes it a suitable material to establish where a person was originally from. Bones are also useful as they help provide information about the burial site.</p>
<p>We use strontium isotopes to help with resolving the issue of provenance: the place where people belong. </p>
<h2>The abundance of isotopes</h2>
<p>The element strontium (chemical symbol, Sr) has an atomic number of 38 and four forms known as isotopes, ⁸⁴Sr, ⁸⁶Sr, ⁸⁷Sr and ⁸⁸Sr. Although these isotopes are stable, their natural abundance changes.</p>
<p>In particular, the amount of ⁸⁶Sr and ⁸⁷Sr in rock varies depending on the age of the rock and when it formed.</p>
<p>But strontium doesn’t just stay in rocks. When rocks break down, these isotopes end up in soil and water, where they are taken up by plants, animals and humans. </p>
<p>So for people it’s not simply a case of “you are <em>what</em> you eat”, but also “you are <em>where</em> you ate”. Our bodies become an isotope record of where we have been and what we have eaten. </p>
<p>One Elder from the advisory committee set up for this project, Gudjugudju, put it succinctly when he said that our ancestors carry the signature of their country in their bones and their teeth.</p>
<h2>A new look at Far North Queensland</h2>
<p>Before strontium isotopes in human teeth can be used to determine their place of origin we must first know how the element in the landscape changes. </p>
<p>We sampled strontium isotopes throughout Cape York to build a series of maps that can show where people may have grown up. These maps were developed and created in close consultation with an <a href="https://theconversation.com/poor-health-in-aboriginal-children-after-european-colonisation-revealed-in-their-skeletal-remains-106616">Aboriginal advisory committee representing several Cape York Aboriginal communities</a>.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=730&fit=crop&dpr=1 600w, https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=730&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=730&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=917&fit=crop&dpr=1 754w, https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=917&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/261806/original/file-20190304-110123-1s8tkkt.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=917&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">One of many new maps: Cape York strontium isotope results can be used to match human values to environmental signals in soil, plants and water.</span>
<span class="attribution"><a class="source" href="https://doi.org/10.1002/gea.21728">Shaun Adams et al. 2019</a>, <span class="license">Author provided</span></span>
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<p>Our results demonstrate that Australia’s ancient and diverse geology culminates in a wider range in strontium isotopes than found <a href="https://www.sciencedirect.com/science/article/pii/S0883292717304134">in overseas studies</a>.</p>
<p>We also found that strontium isotope signatures were transferred relatively unaltered from the geology through the hydrology and finally biology, ie. from the land to water, animals and humans. </p>
<p>For Cape York, we now have a partially complete <a href="https://theconversation.com/dna-from-ancient-aboriginal-australian-remains-enables-their-return-to-country-108168">genomic map</a> and a comprehensive isotopic map that Aboriginal groups can use as a tool to help determine the provenance of their ancestors. </p>
<h2>… but there’s a catch</h2>
<p>The Queensland Museum holds a large number of ancestral remains whose place of origin is still unknown. But current museum policy does not allow for invasive testing on ancestral remains without community consent. </p>
<p>This presents something of a “Catch 22”.</p>
<p>Aboriginal committees in other parts of the country have been thinking about how to return remains where there is no information on where they came from.</p>
<p>The <a href="https://www.aboriginalheritagecouncil.vic.gov.au/">Victorian Aboriginal Heritage Council</a>, which is the peak Aboriginal advisory committee for Victoria, has developed a policy, <a href="https://www.aboriginalheritagecouncil.vic.gov.au/report-ancestral-remains">Bringing the Ancestors Home</a>, that identifies the need to develop an approach to more seamlessly see the repatriation of ancestral remains to descendant communities.</p>
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Read more:
<a href="https://theconversation.com/poor-health-in-aboriginal-children-after-european-colonisation-revealed-in-their-skeletal-remains-106616">Poor health in Aboriginal children after European colonisation revealed in their skeletal remains</a>
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<p>The Commonwealth National Advisory Committee for Indigenous Repatriation has developed a concept for a <a href="https://www.theguardian.com/australia-news/postcolonial-blog/2018/mar/04/pressure-builds-for-a-national-keeping-place-for-indigenous-remains">National Resting Place</a> in Canberra for ancestral remains whose descendant communities can’t be identified.</p>
<p>Our research in Far North Queensland, combining isotopes and ancient DNA, provides a new way to help these communities repatriate their ancestors.</p>
<p>A collaboration between science and Aboriginal communities may represent the best way forward for resolving this complex social issue.</p>
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<p><em>If you’re an academic researcher working with a particular element from the periodic table and have an interesting story to tell then why not <a href="https://theconversation.com/au/pitches">get in touch</a>.</em></p><img src="https://counter.theconversation.com/content/112705/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Shaun Adams receives funding from the Australian Research Council. </span></em></p><p class="fine-print"><em><span>Michael Westaway is an ARC Future Fellow and receives funding from the Australian Research Council. </span></em></p>How do you return Aboriginal remains to their place of origin when you have no record of where they came from? Look to a chemical element that’s laid down in teeth as people grow up.Shaun Adams, Isotope Bioarchaeologist Research Fellow, Griffith UniversityMichael Westaway, Future Fellow, Australian Research Centre for Human Evolution, Griffith UniversityLicensed as Creative Commons – attribution, no derivatives.