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Silver is a chemical element with symbol Ag and atomic number 47. The metal occurs naturally in its pure, free form (native silver), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a by-product of copper, gold, lead, and zinc refining. 
Pure silver is nearly white, lustrous, soft, very ductile, malleable, it is an excellent conductor of heat and electricity. It is not a chemically active metal, but it is attacked by nitric acid (forming the nitrate) and by hot concentrated sulfuric acid. It has the highest electrical conductivity of all metals, but its greater cost has prevented it from being widely used for electrical purposes. Silver does not oxidise in air but reacts with the hydrogen sulfide present in the air, forming silver sulfide (tarnish). This is why silver objects need regular cleaning. Silver is stable in water.