A gold bar is a rectangular piece of gold that is typically produced by a mint or a refinery. It is often used as a standard measure of gold bullion, which is gold that is traded based on its weight and purity. Gold bars come in various sizes, with the most common weighing 400 troy ounces, known as a London Good Delivery bar. Gold bars are valued for their intrinsic worth and are often stored in secure locations like banks or vaults. Investors purchase gold bars as a way to hedge against inflation or economic uncertainty, making them a popular choice in the precious metals market.