No one knows when gold was discovered, nor does anyone know who discovered it. Gold has been known to humankind since prehistory and is mentioned in many ancient texts.
Gold is an elemental metal and is one of the few metals that is not silver or gray in color. Instead, pure gold is bright yellow. It is dense and soft enough to be hammered into very thin sheets and pulled into ? very thin wire. Because it is so soft, it is often alloyed with other metals, such as copper and nickel, to make wearable jewelry.
Gold is not very reactive and does not tarnish, as can be seen in works like the death mask of King Tutankhamun, which has been dated circa 1323 BCE.
Gold has long been used as money but also as a material in electronics and art. It can be beaten to such thinness that it becomes transparent. This way it is used in space helmets, windows, airplane cockpits and as an expensive CD layer. It's also added to paint or to glass to give it a rich red color. Gold can be used in photography and as embroidery thread. It is also nontoxic and can be eaten, although it has no nutritional value.