Jarosite
KFe₃³⁺(SO₄)₂(OH)₆

     Jarosite, a member of the alunite group, is moderately rare at
Mont Saint-Hilaire.

PHYSICAL CHARACTERISTICS:

Color is usually yellow.
Luster is dull to resinous.
Diaphaneity is translucent.
Crystal System is hexagonal; R3m.
Crystal Habits include powdery coatings on feldspar crystals.
Cleavage {001} is distinct.
Fracture is conchoidal to uneven.
Hardness is 2.5 - 3.5
Specific Gravity is approximately 3.15 g/cm³.
Streak is yellow.
Associated Minerals include gypsum.
Distinguishing Features: none.
Origin: Named in 1852 after its discovery locality, in Baranco
   Jaroso, Sierra Almagrera, Spain.

CLASSIFICATION:

REFERENCES:
MinRrec 21:315 (1990), Dana 8:634-635 (1997)

DISTRIBUTION AND RARITY AT MONT SAINT-HILAIRE:

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