Weilite

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Chris.urs-o (talk | contribs) at 18:39, 4 December 2016. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Weilite
General
CategoryArsenate mineral
Formula
(repeating unit)
CaHAsO4
Strunz classification8.AD.10
Crystal systemTriclinic
Crystal classPinacoidal (1)
(same H-M symbol)
Space groupP1
Unit cella = 7.059 Å, b = 6.891 Å
c = 7.201 Å; α = 97.43°
β = 103.55°, γ = 87.75°; Z = 4
Identification
ColorWhite
Crystal habitPowdery, massive
FractureIrregular/uneven
TenacityBrittle
LusterWaxy, greasy, dull
StreakWhite
DiaphaneityTranslucent
Specific gravity3.48
Optical propertiesBiaxial (-)
Refractive indexnα = 1.644 nγ = 1.688
Birefringenceδ = 0.044
2V angleMeasured: 81°
References[1][2][3]

Weilite (CaHAsO4) is a rare arsenate mineral. It is a translucent white triclinic mineral with a waxy luster.[1]

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