Gold

Gold is a chemical element; its chemical symbol is Au and atomic number 79. In its pure form, it is a bright-metallic-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal, a group 11 element, and one of the noble metals. It is one of the least reactive chemical elements, being the second lowest in the reactivity series, with only platinum ranked as less reactive. Gold is solid under standard conditions. Gold often occurs as the free element, as nuggets or grains, in rocks, veins, and alluvial deposits. It occurs in a solid solution series with the native element silver, naturally alloyed with other metals such as copper, platinum, and palladium, as well as mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium. Gold is resistant to most acids, though it does dissolve in aqua regia, forming a soluble tetrachloroaurate anion.

Data Source : Wikipedia