Bismuthinite is a mineral composed of bismuth sulfide and it often occurs with lead and copper ore, and bismite is composed of bismuth oxide. The isolation techniques used to extract pure bismuth from these ores is relatively simple. Most of the bismuth collected for commercial uses is extracted as a by product from copper, gold, lead, silver, and tin processing. Smelting processes used to separate these ores results in bismuth isolation. Smelting is a type of extractive metallurgy that is used to isolate metals from the ores that they are found in. During the smelting process, carbon in the form of coke serves as a reducing agent to reduce the oxidized states of the ore. This process can be used on bismuth by-products from ore processing, or directly on the bismite mineral. The carbon reacts with the oxygen producing carbon monoxide, or carbon dioxide, to leave the metal. Contaminants usually remain, and additional reduction using charcoal or coke further reduce and isolate the bismuth.
