Gold is one of the rarest metals in the world, and has a long history as a valuable and intensely sought-after element. The precious metal has served as the basis for physical currency for thousands of years, and many monetary systems throughout human history have utilized a gold standard that focused on the precious metal. Exploration and production of gold has become a major industry in regions that maintain significant deposits of the metal, and quests for gold have been the impetus of countless expeditions and discoveries [for more gold news and analysis subscribe to our free newsletter].