Image: Andrew Silver (Public domain)
trigonalcommonSulfates
Jarosite
KFe3(SO4)2(OH)6
The image displays a yellowish-brown to brown, finely crystalline to earthy aggregate of Jarosite, showing a somewhat granular texture.
Jarosite Physical Properties
Mohs Hardness
2.5Crystal System
trigonalLuster
vitreousStreak Color
pale yellowCleavage
distinct on {0001}Fracture
unevenSpecific Gravity
3.15Colors
yellow, yellowish-brown, brownTransparency
translucentType Locality
worldwide in oxidized sulfide depositsMineral Group
SulfatesUses
indicator mineral, minor ore of potassium, scientific interestAssociated Minerals
pyrite, goethite, limonite, other sulfatesRarity
commonGeological Context
Jarosite is a secondary mineral that forms in the oxidized zones of sulfide ore deposits, particularly those rich in pyrite, where it results from the alteration of iron sulfides in acidic, sulfate-rich environments.
