gold
Gold is a chemical element, the chemical symbol is Au, and the atomic number is 79. Gold is a popular precious metal that has been used for many centuries as money, preserve and jewelry. In nature, gold appears in the rocks of gold or gold, underground veins and alluvial layers. Kim is also one of the currency metal. Gold at room temperature for the solid, high density, soft, bright, corrosion resistance, its ductility and ductility are the highest in the known metal. Pure gold bright yellow is traditionally considered to be attractive. Before the end of the Bretton Woods agreement, gold was the cornerstone of the gold-based monetary system. The gold bar's ISO currency code is XAU. Gold in the modern industrial application level of dentistry and electronics. Traditionally, gold's high resistance to oxidative erosion is one of the reasons people use it. ...