Chromite
Description
A naturally occurring ore of Chromium. Chromite is composed of oxides of Iron and chromium and may contain Magnesium and Aluminum. Chromite is a black to dark brown color stone with a metallic luster. It looks like Magnetite but has poor magnetic properties. Chromite is found in South Africa, Rhodesia, Cuba, Turkey, the Philippines, India, Japan, Greece, Albania, Russia, Finland, Zimbabwe, western Europe, New Caledonia, Brazil, and the United States (Maryland, Texas, Pennsylvania, California, Oregon, Wyoming, North Carolina).
Synonyms and Related Terms
iron chromite; chrome iron ore; ferrous chromite; Chromeisenstein (Deut.); Chromit (Deut.); chromiet (Ned.); chromita (Port.)
Physical and Chemical Properties
- Isometric crystal system with octahedral crystals; often granular or compact.
- No distinct cleavage.
- Fracture = conchoidal; brittle.
- Luster = submetallic to metallic.
- Streak = dark brown.
- Slightly magnetic.
| Composition | FeCr2O4 |
|---|---|
| CAS | 1308-21-2 |
| Mohs Hardness | 5.5 |
| Density | 3.6 gml |
Resources and Citations
- Mineralogy Database: Chromite
- Encyclopedia Britannica, http://www.britannica.com Comment: "chromite" [Accessed December 11, 2001
- C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
- G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 193
- Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
- Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
- Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
- Wikipedia: http://en.wikipedia.org/wiki/Chromite (Accessed Sept. 2, 2005 for foreign language terms); specific gravity = 4.5-4.8