There are people who make investments in something and consider it just that, but there are others whose curiosity gets peaked. When they buy gold coins or invest in other forms of the precious metal, they want to find out how the product is made. They wonder where gold comes from and how a gold refinery works.
A gold mine sources the ore and processes it at the mine site. This creates a gold metal of low purity that is poured into dore bars. These bars are taken to refineries in order to be purified further. Refining is the final stage of the process of gold production. It is the act of removing any impurities still present after the precious metal is smelted. A refining company receives scrap gold and gold dore bars and places this metal into a furnace in order to re-liquefy it.
Soda ash and borax are added to the melted metal in order to separate the gold from the other metals. A sample of this gold is taken to a lab for testing that will quantify the gold content. These tests, called assays, usually reveal a gold purity of 99.9 percent. This gold is then cast into bars, also referred to as gold bullion.
After the gold has taken bar form, several things will happen, dependent upon the use of the gold. If it will be used in jewelry making, it will be too soft to work with in its pure gold form. Other metals are added to form an alloy and the names of colors are used to designate different alloy types. One example is white gold, the combination of silver, palladium, or nickel with gold.
The gold refinery makes money by charging for the assays and it pays a lower price for the gold content of the item than what gold is trading for on a given day. Refining gold is not an inexpensive process and there are alternatives to taking the precious metal to a refinery. Some companies sell systems that allow individuals to refine their own gold.