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47. SilverName: Silver
Silver is somewhat rare and expensive, although not as expensive as gold. Slag dumps in Asia Minor and on islands in the Aegean Sea indicate that man learned to separate silver from lead as early as 3000 B.C. Pure silver has a brilliant white metallic lustre. It is a little harder than gold and is very ductile and malleable. Pure silver has the highest electrical and thermal conductivity of all metals, and possesses the lowest contact resistance. Silver iodide, AgI, is (or was?) used for causing clouds to produce rain. Silver is stable in pure air and water, but tarnishes when exposed to ozone, hydrogen sulphide, or air containing sulphur. It occurs in ores including argentite, lead, lead-zinc, copper and gold found in Mexico, Peru, and the USA. Silver itself is not toxic but most of its salts are poisonous and may be carcinogenic. Compounds containing silver can be absorbed into the circulatory system and become deposited in various body tissues leading to the condition called argyria which results in a permanent grayish pigmentation of the skin and mucous membranes. Although this condition does not harm a person's health, it is disfiguring. This metal plays no natural biological role in humans. The possible health effects of silver are a subject of dispute. Silver has germicidal effects and kills many microbial organisms in vitro without causing noticeable harm to more complex life-forms. Hippocrates, the father of modern medicine, wrote that silver had beneficial healing and anti-disease properties. Various kinds of silver compounds are sold as remedies for a variety of diseases. However, no clinical study has yet demonstrated a therapeutic use for silver as an antibiotic in vivo. Ingestion of silver compounds can lead to argyria. Silver compounds are used to accelerate healing in burn victims. According to Dr. Robert O. Becker, they can promote the healing of bones as well. Silver (Anglo-Saxon, Seolfor siolfur; Ag is from the Latin argentum) has been known since ancient times. It is mentioned in the book of Genesis and slag heaps found in Asia Minor and on the islands of the Aegean Sea indicate that silver was being separated from lead as early as the 4th millennium BC. Silver has been used for thousands of years as ornaments and utensils, for trade, and as the basis for many monetary systems. It was long considered the second most precious metal, second only to gold. Associated with the moon, as well as with the sea and various lunar goddesses, the metal was referred to by alchemists by the name luna. Quick links
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