Scorodite

Scorodite is a common hydrated iron arsenate mineral, with the chemical formula FeAsO4·2H2O. It is found in hydrothermal deposits and as a secondary mineral in gossans worldwide. Scorodite weathers to limonite.

Scorodite
Scorodite-scoro-35a.jpg
General
CategoryArsenate minerals
Formula
(repeating unit)
FeAsO4·2H2O
Strunz classification8.CD.10
Crystal systemOrthorhombic
Crystal classDipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space groupPcab
Unit cella = 8.937 Å, b = 10.278 Å
c = 9.996 Å; Z = 8
Identification
ColorGreen, blue-green, grey, grayish-green, blue, yellow-brown, nearly colorless, violet
FractureSub-Conchoidal
Mohs scale hardness3.5-4
LusterSub-Adamantine, Vitreous, Resinous
StreakGreenish-White
DiaphaneityTranslucent
Densitymeasured: 3.27 g/cm3 calculated: 3.276 g/cm3
Optical propertiesBiaxial (+)
PleochroismWeak
2V angleMeasured: 40° to 75° Calculated: 46° to 80°
Dispersionrelatively strong r > v
References[1]

Scorodite was discovered in the Schwarzenberg, Saxony district, Erzgebirge, Saxony, Germany. Named from the Greek Scorodion, "garlicky". When heated it smells of garlic, which gives it the name.

ReferencesEdit

Further readingEdit

  • Palache, C., H. Berman, and C. Frondel (1951) Dana's system of mineralogy, (7th edition), v. II, pp. 763–767

External linksEdit