CHALCANTHITE

CLASS: Sulfate . . . CHEMICAL FORMULA: Cu (SO4) . 5H20 . . . CRYSTAL SYSTEM: triclinic
CRYSTAL FORM: pinacoid; tabular or prismatic crystals; stalactitic, botroidal, massive forms.
COLOR: blue
PHYSICAL PROPERTIES: soft (2,5 Mohs), light (2,28 g/cm3), fragile, imperfect exfoliation, conchoidal fracture, translucent, vitreous or resinous luster, very soluble in water.
CURIOSITIES: it is related to aid in decision making.