Millesimal Fineness

Millesimal fineness is a system of denoting the purity of silver alloys by parts per thousand of pure metal by mass in the alloy. For example, an alloy containing 75% silver is denoted as “750″.

The millesimal fineness is usually rounded to a three figure number, particularly where used as a hallmark, and the fineness may vary slightly from the traditional versions of purity.

Common Silver Purities in Millesimal Fineness

999.9 (Ultra-fine silver used by Royal Canadian Mint in the Canadian Silver Maple Leaf)
999 (Fine silver used in Good Delivery bullion bars, also known as three nines fine)
980 (common standard used in Mexico ca.1930 – 1945)
958 (equivalent to Britannia silver)
950 (equivalent to French 1st Standard)
925 (equivalent to Sterling silver)
900 (equivalent to Coin silver in the USA, also known as one nine fine)
833 (common standard used in continental silver especially among the Dutch, Swedish, and Germans)
830 (common standard used in older Scandinavian silver)
835 (a standard predominantly used in Germany after 1884)
800 (minimum standard for silver in Germany after 1884; Egyptian silver; Canadian silver circulating coinage)
750 (uncommon silver standard found in older German, Swiss and Austro-Hungarian silver)

Related Links

How Much Is Silver Worth