Crystals of azurite belong to the monoclinic system; they have a vitreous lustre and are translucent.
The crystals of prismatic habit represented in figs.
It forms monoclinic crystals which are very soluble in water.
Crystals have the form of small, sharply defined cubes of an oliveor grass-green colour, and occur together in considerable numbers on the matrix of the specimens.
Cesena and Perticara are well-known localities in this district, the latter yielding crystals coated with asphalt.