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
General
CategoryArsenate minerals
Formula
(repeating unit)
FeAsO4·2H2O
IMA symbolScd[1]
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[2]

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

References

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  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ http://www.mindat.org/min-3595.html Mindat data

Further reading

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