Azurite
Azurite is a copper mineral which has similar origins to malachite, but is more frequently in crystalline form. However, azurite is found less commonly than malachite. Occasionally, azurite crystals are replaced by malachite, known as pseudomorphs. Azurite is characterized by its deep blue color. Fresh unweathered azurite has a vitreous luster.
Chemistry: carbonate of copper ♦ opaque ♦ Luster: vitreous ♦ Crystal system: Monoclinic prismatic ♦ Moh's hardness: 3.5-4 ♦ Color: Deep blue ♦ Localities: Found in many areas of the world. Two famous U.S. localities: Bisbee and Morenci in Arizona