FormulaCuSO4 • 5H2O
OriginPlanet Mine, La Paz (USA)
DescriptionIntense blue coloured cluster of chalcanthite crystals 
Classification (Lapis) Sulfates
Crystal Systemtriclinic
Hardness2,5
ColourBerlin blue to sky-blue, greenish blue; colorless to pale blue in transmitted ligh
Streakwhite 
Luminescenceblue 
Lustervitreous
Transparency (Opacity)translucent
Cleavageperfect
Fractureuneven
Magnetismnegative
Geological Settinga secondary mineral in the oxidized portions of copper sulfide deposits
Specific Gravity2,28 g/cm3