Galena cubic unit cell much like the mineral halite of the halide mineral group. Zinc, cadmium, iron, copper, antimony, arsenic, bismuth and selenium also occur in variable amounts in galena. Selenium substitutes for sulfur in the structure constituting a solid solution series. The lead telluride mineral altaite has the same crystal structure as galena. Within the weathering or oxidation zone galena alters to anglesite (lead sulfate) or cerussite (lead carbonate). Galena exposed to acid mine drainage can be oxidized to anglesite by naturally occurring bacteria and archaea, in a process similar to bioleaching. One of the oldest uses of galena was
Iron ore foundry iron should have less than 0.15% sulfur. In the rest of the world a high sulfur cast iron can be used for making castings, but will make poor wrought iron. There are a number of remedies for sulfur contamination. The first, and the one most used in historic and prehistoric operations, is avoidance. Coal was not used in Europe (unlike China) as a fuel for smelting because it contains sulfur and therefore causes hot short iron. If an ore resulted in hot short metal, ironmasters looked for another ore. When mineral coal was first used in European blast furnaces