Introduction

Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a transition metal. It is one of the least reactive solid chemical elements.Gold has been a valuable and highly sought-after precious metal for coinage, jewelry, and other arts since long before the beginning of history. . Gold has also been frequently linked to a wide variety of symbolism and ideologies. A total of 165,000 tonnes of gold have been mined in human history, as of 2009.