High Precision Soft Magnetic Alloy For Medical Equipments ISO Standard

Pure Silver 9999/ Sterling Silver 925 Strip/ Tape/ Sheet for Medical Equipments

Pure silver, also referred to as fine silver, has actual silver content of 99.9%. Because of its high purity, fine silver is too soft to use in jewelry making and is often mixed with other metals to make it harder.

· Fine silver has a millesimal fineness of 999. Also called pure silver, or three nines fine, fine silver contains 99.9% silver, with the balance being trace amounts of impurities. This grade of silver is used to make bullion bars for international commodities trading and investment in silver. In the modern world, fine silver is understood to be too soft for general use.

· Britannia silver has a millesimal fineness of at least 958. The alloy is 95.84% pure silver and 4.16 per cent copper or other metals. The Britannia standard was developed in Britain in 1697 to help prevent British sterling silver coins from being melted to make silver plate. It was obligatory in Britain between 1697 and 1720, when the sterling silver standard was restored. It became an optional standard thereafter.

· The French 1st standard has a milessimal fineness of 950. The French 1st alloy is 95% silver and 5 per cent copper or other metals.

· 91 zolotnik Russian silver has a millesimal fineness of 947. The zolotnik (Russian золотник, from the Russian zoloto, or золото, meaning gold) was used in Russia as early as the 11th century to denote the weight of gold coins. In its earliest usage, the zolotnik was 1/96 of a pound, but it later was changed to represent 1/72 of a pound. Ninety-one (91) zolotniks have the equivalent millesimal fineness of 947[9]. Thus, the alloy contains 94.79% pure silver and 5.21 per cent copper or other metals.

· Sterling silver has a millesimal fineness of 925. The sterling silver alloy is 92.5% pure silver and 7.5 per cent copper or other metals.

· 88 zolotnik Russian silver has the equivalent millesimal fineness of 916. The alloy contains 91.66% pure silver and 8.34 per cent copper or other metals. (The description of the zolotnik is above.)

· Coin silver has a millesimal fineness of 900. The term "coin silver" was derived from the fact that much of it was made from melting down silver coins. It is important here to note that there are differences between the coin silver standard and the coin silver alloy, as actually used in making silver objects. The coin silver standard in the United States was 90% silver and 10% copper, as dictated by US FTC guidelines. However, in silversmithing, coins could come from other nations besides the United States, and thus coin silver objects could vary from 750 millesimal fineness (75% silver) to 900 (90% silver). Coins were used as a source of silver in the US until 1868, shortly after the discovery of the Comstock silver lodes in Nevada, which provided a significant source of silver. Around this time the sterling standard was adopted by the American silver industry.