silver: e.g. Flowing Hair and 1837–1964 U.S. silver coins. Also used in U.S. silver commemorative coins and silver proof coins 1982–2018. 892.4: US coinage fine "standard silver" as defined by the Coinage Act of 1792: e.g. Draped Bust and Capped Bust U.S. silver coins (1795–1836) 875: 84 zolotnik is the most common fineness for Russian silver. Swiss standard, commonly used for export watchcases (also 800 and later 935). 835: a standard predominantly used in Germany after 1884, and for some Dutch silver; and for the minting of coins in countries of the Latin Monetary Union 833: () a common standard for continental silver especially among the Dutch, Swedish, and Germans 830: a common standard used in older Scandinavian silver 800: the minimum standard for silver in Germany after 1884; the French 2nd standard for silver; "plata de segunda ley" in Spain (second law silver); Egyptian silver; Canadian silver circulating coinage from 1920-1966/7 750: an uncommon silver standard found in older German, Swiss and Austro-Hungarian silver 720: Decoplata :many Mexican and Dutch silver coins use this standard, as well as some coins from Portugal's former colonies, Japan, Uruguay, Ecuador, Egypt, and Morocco. 600: Used in some examples of postwar Japanese coins, such as the 1957-1966 100 yen coin 500: Standard used for making British coinage 1920–1946 as well as Canadian coins from 1967-1968, and some coins from Colombia and Brazil. 400: Standard used for US half dollars between 1965 and 1970, and commemorative issue Eisenhower dollars between 1971 and 1978. Also used in some Swedish Krona coins. 350: Standard used for US Jefferson 'War Nickels' minted between 1942 and 1945. Karat The karat (US spelling, symbol K or kt) or carat (UK spelling, symbol C or ct) is a fractional measure of purity for gold alloys, in parts fine per 24 parts whole. The karat system is a standard adopted by US federal law. Mass K = 24 × Mg / Mm where K is the karat rating of the material, Mg is the mass of pure gold in the alloy, and Mm is the total mass of the material. 24-karat gold is pure (while 100% purity is unattainable, this designation is permitted in commerce for 99.95% purity), 18-karat gold is 18 parts gold, 6 parts another metal (forming an alloy with 75% gold), 12-karat gold is 12 parts gold (12 parts another metal), and so forth. In England, the carat