Article · Wikipedia archive · Last revised Jul 23, 2026

Weilite

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

Last revised
Jul 23, 2026
Read time
≈ 1 min
Length
164 w
Citations
8
Source
Weilite
Weilite (white) with pink erythrite from Richelsdorf District, Wildeck, Hesse, Germany
General
CategoryArsenate mineral
FormulaCaHAsO4
IMA symbolWei1
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°
References234

Weilite (CaHAsO4) is a rare arsenate mineral. It is a translucent white triclinic mineral with a waxy luster.2

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.2 It occurs in the oxidized zone of arsenic-bearing hydrothermal veins. It occurs as an alteration product of pharmacolite and haidingerite.34

References

References