Gold Coins
Gold coins are one of the oldest forms of money. The first gold coins in history were coined by the Lydian king Croesus in about 560 BC, not long after the first silver coins were minted by king Pheidon of Argos in about 700 BC. more...
Gold coins then had a very long period as a primary form of money, only falling into disuse in the early 20th century. Most of the world stopped making gold coins as currency by 1933.
Bullion coins
Other than ancient gold coins, gold bullion coins are popular among people who desire a "hedge" against currency inflation or store of value. South Africa introduced the Krugerrand in 1967 to cater to this market; this was the reason for its convenient and memorable gold content—exactly one troy ounce. It was the first modern, low premium (i.e. priced only slightly above the bullion value of the gold) bullion gold coin. Bullion coins are also produced in fractions of an ounce – typically half ounce, quarter ounce, and one-tenth ounce. Gold is internationally recognised as a form of currency under ISO 4217. Other bullion coins, many named after features on their design, include the Swiss Vreneli, Gold dinar, Australian Gold Nugget, Australian Kookaburra, British Britannia, Canadian Gold Maple Leaf and Chinese Panda.
Counterfeits
There are well made counterfeit gold coins are in circulation. For example, the Saint-Gaudens omega counterfeit is infamous for it's complexity; and has fooled many numismatics experts. It is a high relief business strike, and due to the extensive wear on the die, these coins were not made for many years. For poor counterfeits, a good scale can usually tell if it's counterfeit or not; however, there are many well made counterfeited ancient coins that not only use gold, but the correct amount as well.
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