Hashemite, Ba(Cr,S)O4, a new mineral from Jordan.

P. L. Hauff; E.E. Foord; S. Rosenblum

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USGS · 70011268

Hashemite, Ba(Cr,S)O4, a new mineral from Jordan.

P. L. Hauff·E.E. Foord·S. Rosenblum

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Abstract

Hashemite, Ba(Cr,S)O4, the isostructural chromate analogue of baryte, has been found in west-central Jordan. It is associated with chromian ettringite, apatite and calcite in a phosphatic carbonate rock analogous to the Hatrurim formation in Israel. The mineral is orthorhombic, Pnma, with a 9.112(2), b 5.541(1), c 7.343(1) A, Z = 4. Strongest XRD lines are 3.516(100), 3.171(80), 3.669(60), 2.175(60), 2.150(45) A. Hashemite occurs as small, euhedral, dark brown, commonly zoned crystals with an average D 4.59 g/cm3 and H. 31/2. It is biaxial positive; dark varieties have alpha 1.952(2), beta 1.960(2), gamma 1.977(2); light varieties have alpha 1.810(2), beta 1.813(2), gamma 1.824(2), 2Vgamma 35o-57o.-J.A.Z.

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P. L. Hauff, E.E. Foord, S. Rosenblum. 1983. Hashemite, Ba(Cr,S)O4, a new mineral from Jordan.. https://pubs.usgs.gov/publication/70011268

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