Chromium Elements, Alloys and Symbols

• Chromite, FeCrO₄with MgCrO₄. 
• Crocoite, PbCrO₄.

Chromite, or chromite iron ores, is the chief source of chromium. Its production in the United States is very small, coming mostly from Shasta County, California. It has also been found in workable deposits in Pennsylvania, Maryland, North Carolina and Wyoming. Large amounts of the ore are impoted from British South Africa; Portugese  East Africa; Greece; India; and Cuba. Chromium is used as a steel-hardening metal. It gives to steel a superior harness and if added in the proper proportion does not produce brittleness. Chromium is used in plating and in certain non-iron alloys. The mineral chromite is made into bricks that are used as linings in metallurgical furnaces. Various red, orange and green pigments and dyes are made from chromium compounds. Chromium salts are used as mordants in the dyeing and printing of cloth. Chromium compounds are useful in tanning leather.