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GENERAL
Tin is one of the few metals that has been used and traded by humans for more than 5000 years. As tin is easy to melt, our ancestors were You might have heard of tin soldiers and tin whistles, but today the biggest use of tin is to make cans for packaging food, which keep important things in your kitchen cupboard, such as Baked Beans for you or Pal for your dog, fresh for long periods of time.
PROPERTIES
SOURCEAustralia does not produce large quantities of tin by world standards, but we do mine deposits of tin ore in Tasmania and, to a lesser extent, Western Australia (in Greenbushes). Tin ore was first discovered in Australia in the 1880s, and in fact the Renison Bell mine in Tasmania (named after George Renison Bell, the prospector and explorer who first staked a claim in the area) is one of the largest underground tin mines in the world. Tin ore is mined either underground or by bucket-line dredging, depending on the location of the ore. The tin ore is separated from waste rock by gravity methods such as shaking tables and spirals, as it is relatively heavy. To obtain pure tin, the ore is then heated with carbon in a smelting process, then further refined by heating.
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AMAZING FACTS About 300 BC, the Chinese developed a crossbow made from bronze, enabling them to defeat the Mongolians who were using ordinary long bows with less range and penetrating power. The Chinese were thus able to open up trade routes with Western Asia and Europe, ending 3000 years of Chinese isolation. In the first century AD, the Romans used tin to make bronze items, and lead-tin solder. They also used tin to make pewter items (like cups, plates and ornaments) made from 70% tin and 30% lead, which was dangerous given that lead is poisonous! In 618 AD, tin was exchanged by Britain for corn from Alexandria, to help relieve a famine. In the phrase ‘Tinker, tailor, soldier, sailor……’ the word tinker probably comes from the tin pots and pans that tinkers (often gypsies) mended in Old England. During the 18th century, pewter figurines were very popular to own, such as ‘tin soldiers’. In the late 18th century in China, tin was first beaten into thin sheets and used to line tea chests. In 1795, Napoleon Bonaparte offered a prize for anyone who could find a way of keeping food fresh for longer (for his soldiers). So a Frenchman called Nicholas Appert discovered that food boiled in glass bottles, then immediately sealed, would keep for several months. Then in 1810 an Englishman, Peter Durand, patented the first tinplate food container. In 1825, a ship carrying tinned foods (pea soup and beef) to the Arctic sank, yet nearly 100 years later some of the containers were recovered and the contents were still fresh enough to eat! Church bells are made of bronze, with a high tin content, giving them a wonderful resonating sound. Famous bells include those in Westminster Abbey, the ‘Oranges and Lemons’ bells of St Clements, and the largest bell in the world in Moscow which weighs about 130 tonnes (Big Ben only weighs about 15 tonnes). |
able to alloy tin with copper to make bronze. Tin was therefore an important metal in our history and development, taking us from the Stone Age to the Bronze Age. Bronze could be sharpened and used in tools and weapons, and people started to go in search of tin, venturing into other lands to trade goods.
