Gold is a chemical element called Au, whose atomic number is 79;is therefore one of the few elements with high atomic numbers that are naturally available at the same time. It is found in nature in the form of a yellowish-red, high density, retractable and knockable metal . Gold is classed chemically from transition metals and within the eleventh group in the periodic table ; it is also classified as noble metals . It is not affected by most common acids , except in royal water , a mixture of nitric acid and hydrochloric acid .

Gold is found in its free form, sometimes in the form of pieces or granules within rocks, or in the form of veins in the ground, or in silt on the riverbed. On the whole, gold is relatively rare] It is sometimes found in the form of a rigid solution with silver metal in the electrode alloy; it also forms natural alloys with copper and palladium ;

Gold is a precious metal used in coins and jewelry , in addition to the works of art ofmany peoples, civilizations and nations over time . Gold plays an important role in global economic performance, so gold cover and reserves have an impact on monetary policiesin the world. There is a total of about 186,700 tons of gold in the world according to 2015 data;  China leads the world production by about 450 tons per year. World consumption of newly produced gold is distributed as follows: around 50% in jewelery, 40% in investments and about 10% in industry. Due to its characteristic properties in terms of suction capacity, methods, electrical conductivity and corrosion resistance, gold has an applied industrial importance, especially in electronic fields.