Weilite
Weilite (CaHAsO4) is a rare arsenate mineral. It is a translucent white triclinic mineral with a waxy luster.[1]
| Weilite | |
|---|---|
| General | |
| Category | Arsenate mineral |
| Formula (repeating unit) | CaHAsO4 |
| Strunz classification | 8.AD.10 |
| Crystal system | Triclinic |
| Crystal class | Pinacoidal (1) (same H-M symbol) |
| Space group | P1 |
| Unit cell | a = 7.059 Å, b = 6.891 Å c = 7.201 Å; α = 97.43° β = 103.55°, γ = 87.75°; Z = 4 |
| Identification | |
| Color | White |
| Crystal habit | Powdery, massive |
| Fracture | Irregular/uneven |
| Tenacity | Brittle |
| Luster | Waxy, greasy, dull |
| Streak | White |
| Diaphaneity | Translucent |
| Specific gravity | 3.48 |
| Optical properties | Biaxial (-) |
| Refractive index | nα = 1.644 nγ = 1.688 |
| Birefringence | δ = 0.044 |
| 2V angle | Measured: 81° |
| References | [1][2][3] |
It was first described in 1963 for occurrences in Gabe Gottes Mine, Haut-Rhin, Alsace, France; Wittichen, Schenkenzell, Black Forest, Baden-Württemberg, Germany; and the Schneeberg District, Erzgebirge, Saxony, Germany. It is named after French mineralogist René Weil of the University of Strasbourg.[1] It occurs in the oxidized zone of arsenic-bearing hydrothermal veins. It occurs as an alteration product of pharmacolite and haidingerite.[2][3]
References
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