Xitieshanite is a hydrous iron sulfate–chloride mineral with chemical formula: Fe3+(SO4)Cl·6(H2O).
| Xitieshanite |
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| General |
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| Category | Sulfate mineral |
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Formula
(repeating unit) | Fe3+(SO4)Cl·6(H2O) |
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| Strunz classification | 7.DC.20 |
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| Crystal system | Monoclinic |
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| Crystal class | Prismatic (2/m)
(same H-M symbol) |
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| Space group | P21/a |
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| Unit cell | a = 14.1 Å, b = 6.9 Å
c = 10.67 Å; β = 111.26°; Z = 4 |
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| Identification |
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| Formula mass | 313.47 g/mol |
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| Color | Green; yellow green |
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| Crystal habit | Acicular |
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| Cleavage | Uncertain / indistinct |
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| Fracture | Conchoidal to uneven |
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| Mohs scale hardness | 2.5 - 3 |
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| Luster | Vitreous |
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| Streak | Yellow |
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| Diaphaneity | Transparent to translucent |
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| Specific gravity | 1.99 |
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| Optical properties | Biaxial (-) |
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| Refractive index | nα = 1.536 nβ = 1.570 nγ = 1.628 |
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| Birefringence | δ = 0.092 |
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| Pleochroism | Colorless (x) to pale yellow (y) to light greenish yellow (z0 |
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| 2V angle | Measured: 77° |
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| Dispersion | r > v |
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| References |
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It was discovered in 1983 and named for the discovery location of Xitieshan lead/zinc ore deposit in the Qinghai Province, China.[2] The mineral has also been reported in 2005 from acid mine drainage from a coal mine in Green Valley, Vigo County, Indiana.