A Precious Metal is a metal with rare metallic chemical element and due to that is of high economic value. Precious metals are less reactive than most elements, have high luster, and have higher melting points than other metals. Gold, Platinum and Silver are considered as precious metals and used extensively in jewelry.
Gold
Gold is an extraordinary and rare precious metal, with an unmatched combination of chemical and physical properties. Gold is the most non-reactive of all metals and it does not oxidize under ordinary conditions. No other metal is as malleable as gold. Pure gold is very soft and pliable, and alloys of different other metals are combined with pure gold to enhance its durability and strength, as well as creating a blush in the gold’s appearance with different color tones. 24 karat is 100 % pure gold, and it is more expensive and less durable than gold that is alloyed with other metals.
Platinum
Platinum, an extremely rare and expensive metal, is a silvery gray precious metal often used for setting or mounting high quality diamonds and gemstones. Platinum is a strong, durable and dense metal which is valued for its white color and purity.
Silver
Pure silver is very soft metal with its lustrous white color. Silver is used as jewelry metal well before the development of white gold alloys, and before platinum could be isolated. It is normally stable in pure air and water but tarnishes when exposed to ozone, hydrogen sulfide or sulfur.