Hashemite (mineral)
Hashemite is a very rare barium chromate mineral[1] with the formula Ba(Cr,S)O4.[2] It is a representative of natural chromates - a relatively small and rare group of minerals. Hashemite is the barium-analogue of tarapacáite. It is also the chromium-analogue of baryte, and belongs to the baryte group of minerals. Hashemite is stoichiometrically similar to crocoite and chromatite.[1] Hashemite is orthorhombic, with space group Pnma. I was found together with chromium-bearing ettringite and an apatite group mineral in the Hatrurim Formation,[2] known for the occurrence of rocks formed due to natural pyrometamorphism.[1] Hashemite is named after the Hashemite Kingdom of Jordan.[2]
| Hashemite | |
|---|---|
 Hashemite from the Lisdan-Siwaga Fault, Hashem Region, Amman, Jordan | |
| General | |
| Category | Chromate minerals |
| Formula (repeating unit) | Barium Chromate Ba(S,Cr)O4 |
| Crystal system | Orthorhombic |
| Identification | |
| Color | Brown to yellow |
| Cleavage | Perfect {001}, good {010} {100} |
| Mohs scale hardness | 3.5 |
| Luster | Adamantine |
| Diaphaneity | Translucent |
| Specific gravity | 4.54 - 4.59 |
| References | [1] |
References
- "Hashemite: Hashemite mineral information and data". Mindat.org. Retrieved 5 March 2016.
- Hauff, P.L., Foord, E.E., and Rosenblum, S., 1983. Hashemite, Ba(Cr,S)O4, a new mineral from Jordan. American Mineralogist 68, 1223-1225.
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