Gold is a yellow, soft transition metal with the atomic number 79. It has high thermal and electrical conductivity and is highly unreactive. Gold forms under extreme pressures and temperatures in supernova explosions, then gets ejected and incorporated into new star and planet formations. It is dispersed on Earth through geological processes and accumulates due to its nobility. Gold has been highly valued by humans throughout history for use in jewelry, art, and as a monetary standard due to its rarity, workability, and resistance to corrosion.