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Sterling Silver Jewelry-The Rest Of The Story
By Sam and Tami Serio
Morning Light
Jewelry
Silver is widely diffused but is rarely found in the native state.
Silver is originally as widespread as gold, occurring in nearly all of the
volcanic rocks. Whereas gold remains unaltered by the action of the
elements and is often carried long distances from its original place of
occurrence, silver on the contrary is only to be found in the rocks where
it originally occurs. When these rocks are broken down or worn away, the
silver is either driven into new mineral combinations, or more often
dissipated and lost. Silver, therefore, is only to be obtained by
subterranean mining. Shafts are driven and the ore brought to the surface,
and by use of various processes the silver is extracted, refined and made
ready for commercial purposes.
An old process and one still employed extensively throughout Mexico where
a large quantity of silver is produced, is to take the ore after it has
been crushed or reduced to a fine mud or puddle and spread it about two
feet deep over the floor of a large courtyard. Powered sulfate of copper
is spread over the mass and then horses or mules are driven around in
circle to tread the sulfate in and mix it thoroughly with the ore. After
about one day's treading a quantity of common salt is added and after two
days more treading quicksilver is added. This mass is trodden over for a
period of about fifteen days, and is then shoveled into a large tank
through which a rapid stream of water is passed. This washes away all but
the silver and quicksilver, which is then poured into cone-shaped canvas
bags. Most of the quicksilver runs out leaving the silver, which is then
retorted. The quicksilver is used over and over again to assist in
recovering the silver.
Pure silver has a beautiful white color and luster; it is almost as
plastic as pure gold and like it very soft. Silver does not tarnish in
natural air, but when it comes in contact with sulfur compounds it readily
forms black silver sulfide. The sulfur compounds which act on silver are
found in small quantities in the air as a result of burning coal and
illuminating gas, while larger amounts occur in vulcanized rubber, wool,
and foods like eggs.
Pure silver is too soft to make durable objects that require lightness and
stability of form. This defect is overcome by alloying it with a little
copper.
An alloy of 925 parts fine silver and 75 parts copper is called 925-1000
fine or what is commonly known as sterling silver. This alloy is used
almost universally for jewelry and the best silverware.
The Authors
of the above Article, Sam and Tami Serio have been passionately involved
with Jewelry and Gemstones for over fifteen-years. You are cordially
invited to visit http://www.morninglightjewelry.com for a wealth of
information about the fascinating world of Jewelry and Gemstones. Together
they also shelter 20 abandoned and abused dogs & cats. A portion of their
profits goes to the care and feeding of the animals.
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