Pure silver (Ag) has a melting point of 1761 (F)/ 961 (C) and its specific gravity is 10.49 units, whereas sterling silver has a melting point of 1640 (F)/ 893 (C) and its specific gravity being 10.36 units.Silver is the most popular metal, owing to a number of factors.
(1) It is a precious metal and therefore anything made in silver has intrinsic value.
(2) Silver is a relatively cheap metal with which to work, taking into account the amounts required to produce small pieces of jewelery.
Pure silver, which is known as 'fine silver', is, like fine gold, a very soft metal and is therefore of little use to the jeweler in this form, except as a plating metal. It is therefore alloyed with other metals to produce harder silver alloys. Silver Alloys:
Sterling Silver
Britannia Silver
This is a higher standard of silver alloy containing 958.4 parts fine silver and 41.6 parts copper. {This standard was introduced in England by Act of Parliament in 1697 to replace sterling silver as the obligatory standard for items of "wrought plate". - Wikipedia
One distinct disadvantage of silver is its affinity for atmospheric sulphur, which produces a golden brown stain or tarnish film. When silver is subjected to successive heating, be it for soldering, annealing, casting, etc., the copper in the alloy oxidizes and forms a grey stain on the surface of the metal.
No comments:
Post a Comment