Chromium is a hard, steely-grey, lustrous metal. Chromium is the main additive in Stainless Steel, to which it adds anti-corrosive properties. Chromium is the third hardest element behind Carbon (diamond) and Boron. Chromium minerals as pigments came to the attention of the west in the eighteenth century. During the nineteenth century, Chromium was primarily used not only as a component of paints, but in tanning salts as well. In 1827, a large Chromite deposit was discovered near Baltimore, United States, which quickly met the demand for tanning salts much more adequately than the crocoite that had been used previously in Russia. This made the United States the largest producer of Chromium products until the year 1848, when larger deposits of chromite were uncovered near the city of Bursa, Turkey.
The largest producers of chromium ore in 2013 have been South Africa, Kazakhstan, Turkey and India. The two main products of Chromium ore refining are Ferrochrome and metallic Chrome. For the production of pure Chromium, the Iron must be separated from the Chromium in a two-step roasting and leaching process. The creation of metal alloys account for 85% of the available Chromium’s usage. The remainder is used in the chemical, refractory, and foundry industries. Stainless Steel, the primary corrosion-resistant metal alloy, is formed when Chromium is introduced to Iron in sufficient concentrations, usually above 11%.