A dore bar is a semi-pure alloy of gold and silver, usually created at the site of a mine. It is a product of the mining and refining process and serves as a convenient way to transport and store the precious metals before further refining. The composition of a dore bar can vary significantly, but it typically contains between 80% and 95% gold, with silver and trace amounts of other metals making up the remainder.
Dore bars are produced by pouring the molten metal, obtained from the smelting of gold-bearing ores, into molds. Once the bars have solidified and cooled, they are typically weighed and stamped with identifying information such as the weight, purity, and the producer’s logo.
The dore bars are then shipped to a refinery, where they undergo further processing to remove impurities and increase the purity of the gold and silver content. This refining process can involve a combination of methods, such as pyrometallurgical refining (using high temperatures to separate the metals), electrolysis, or chemical processes like the Miller or Wohlwill processes.
Once the refining process is complete, the gold and silver can be sold as investment-grade bars or coins, or used in various industries, such as electronics, dentistry, and jewelry manufacturing.