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Fascinating Facts About Silver

by Jenifer Adams..via Rock Scoop

Although silver was discovered later than gold and copper it has been known and used by humankind since prehistoric times. Herodotus, the Greek historian, knew of silver used to make coins and beads found in the river sands of the Pactolus in Lydia. The Chinese wrote of silver metals in 2500 B.C. In the earliest prehistoric strata at the site of Troy, considerable deposits of silver and gold treasure have been excavated. Among the artifacts, silver bracelets and gold earrings, ornaments placed in a silver cup and more than 8000 beads were buried in the ancient city 2000 years B.C.

The most ancient silver mines of importance were in Asia Minor and on islands in the Aegean Sea. The Romans obtained most of their silver from Spain until supplies became scarce during the Middle Ages. After the discovery of the Americas in 1492, Mexico became the largest silver producing country in the world.

Silver is a lustrous white metal, widely distributed in nature. In ores, it is commonly associated with gold, lead and copper. Much of the world’s silver is obtained as a by-product of smelting these other metals. Horn-silver (AgCl) is found in the oxidized portions of ore-bearing lodes near the surface. Small amounts of silver in the oxidation zone form as the more complex compounds weather and erode. At deeper levels silver occurs as sulfides, arsenides, antimonides (compounds of silver with sulfur, arsenic and antimony). In these deposits, formation is the result of deposition from primary hydrothermal solutions. Argenite occurs in low temperature hydrothermal veins in association with other silver minerals or sometimes in the cementation zone of lead and zinc deposits.

When found in a metallic state, it is called “native silver”. This usually occurs in dendritic and wire-like forms which are aggregates of minute crystals.

Silver may also occur in thin sheets or in large masses. In Kongsberg, Norway, magnificent crystalline wire specimens occur is association with sulfides, calcite, barite, fluorite and quartz.

The worlds largest specimen of massive silver was mined in Aspen, Colorado, and weighs in at 844 pounds. On the Keweenaw Peninsula of Michigan , small amounts of primary native silver can be found in association with native copper. In Mexico, the Guanajuato Mine has been ion operation since the year 1500 A.D. During that time more than 500 billion kilos of silver have been mined.

About 3/4 of the worlds silver production is used for monetary purposes, either as coins or as bullion that governments hold to redeem paper currency. The leading industrial use is for manufacturing tableware and jewelry. The second largest industrial consumer is the photographic industry (? This may not be true now - ED) Compounded with bromine or chlorine, silver forms the salts which register light and shade on photographic film. Silver has the highest thermal and electrical conductivity of any substance, making it ideal for use in electronic equipment. Silver is second only to gold in malleability. One ounce of silver can be drawn into a wire 30 miles long. A silver leaf can be beaten to a thickness of 1/100,000 of an inch.

via =Cedar Valley Gems 2/99, Gems of the Redwoods 4/06, Gems of the Rogue 6/06—CFMS Newsletter 6/06