Chromium is a transition metal with many uses. It is mined as chromite, a mix of chromium and iron, with significant deposits in South Africa and Kazakhstan.
Anglo American (OTC: AAUKY) - They own 40% of Samancor, the largest producer of ferrochrome.
Norilsk Nickel (OTC: NILSY)
Hebei Chromate Chemical Co. - http://www.chrome-chem.com/
American Elements - http://www.americanelements.com/cr.html - Chromium metal, ferrochromium, chromium silicon alloy, ammonium dichromate, chromium chloride, chromium nitrate, chromium oxide, chromium potassium sulfate, and potassium dichromate.