Silver - Minerals and Uses
Silver has been known and used since ancient times. Evidence in Asia Minor suggests that people were separating silver from lead as long ago as 3000 B.C. Like gold, it is a prized metal, both for its beauty and usefulness.
The chemical symbol of silver is Ag after the Latin word Argentum and it has a bright, metallic luster, and when untarnished, has a white color. Silver is found combined with a number of different elements to form a variety of minerals and ores. It is also found in very small amounts (called trace amounts) in gold, lead, zinc, and copper ores.
As a mineral, silver crystallizes in the cubic (isometric) system. In rare cases it forms crystals. Usually it is found in thin sheets or as long wires and bundles of wires. Silver is rather soft at 2 to 3 on Mohs' hardness scale and is both malleable and ductile.
Silver is found in. A full two-thirds of the silver resources in the world are found in association with lead, zinc, and copper ore deposits. The remaining third is found in association with deposits of gold. The most important ore mineral of silver is argentite (Ag2S).
The significant world producers of silver are Mexico, Peru, Chile, and Canada. A number of other countries produce smaller amounts of silver.
Silver has been used for thousands of years for jewelry and decorative items of all types. Likewise, it has been used for silverware. Of all the metals, untarnished silver is the best reflector of light. As a result, it was used in ancient times to make mirrors. Unfortunately, silver tarnishes very easily and quickly, and its use as a mirror could be frustrating. Sterling silver is silver alloyed with another metal, usually copper. For such an alloy to be called “Sterling” it has to have 92.5% silver content. Silver is also used as a currency and at one time, along with gold, was the standard for the currency of the United States of America. Silver bromide and silver nitrate are used in photography. It is estimated that about one-third of the silver used in the United States is used in various photographic materials and processes. It is also used in electrical products because it conducts electricity so well (silver actually conducts electricity more efficiently than copper). It is used by dentists in amalgam fillings. Silver is also used in the production of bearings.
There are a number of materials and technologies that can be used in place of silver. Stainless steel is used to make tableware. Film with a lower silver content might be used in photography. Digital photography can conceivably significantly reduce the demand for silver-based films. Digital imaging will also reduce the consumption of silver-based films in the printing industry. Rhodium and aluminum can be substituted for silver in making mirrors.
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