Platinum Coins.

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Platinum was first used for minting coins in Spanish-colonized America. Following the discovery of platinum in gold rocks, the Spaniards were unable to use it for a long time because they had no technology for processing this metal. The then-cheap platinum was used for various kinds of frauds, such as substituting it for the more expensive silver. After the discovery that platinum alloys with gold, counterfeiters began to add it to gold coins. The platinum confiscated from counterfeiters was then thrown into the sea, in accordance with the royal decree of 1735. Later, the practice of adding platinum to gold as a ligature was adopted by the authorities in Spain in order to lower the gold content of coins.[1] Also in Spain, in the mid-19th century, counterfeiters began producing British Sovereigns out of a gold-plated alloy of platinum and copper, relying on a similar specific weight of platinum and gold.[2]

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Platinum coins are a form of currency. Platinum has an international currency symbol under ISO 4217 of XPT. The issues of legitimate platinum coins were initiated by Spain in Spanish-colonized America in the 18th century and continued by the Russian Empire in the 19th century. As a form of currency, these coins proved to be impractical: platinum resembles many less expensive metals, and, unlike the more malleable and ductile silver and gold, it is very difficult to work. Several commemorative coin sets have been issued starting from 1978 and became popular among coin collectors. The major platinum bullion coins include the American Platinum Eagle, the Canadian Platinum Maple Leaf, the Australian Platinum Koala, the Isle of Man Noble, the Chinese Platinum Panda and several series by the Soviet Union and later by the Russian Federation. The production of most platinum coins stopped around 2005 except for the American Platinum Eagle â€" one of the world's most popular platinum coins â€" which was still being produced in 2009.