3.5 - 4.0 on the Mohs scale.

Nambia, Arizona, New Mexico, Mexico, Australia, China, France, Greece, Sardinia, Ural Mountains of Russia

Deep blue-black to brilliant "azure" blue in color. Crystals are rare and highly sought after. Azurite is often found along with malachite, or even cuprite.

Like malachite, azurite is occasionally coated with colorless wax, or rarely impregnated with plastic and/or other hardened agents to improve durabilty and appearance.

More information on gemstone enhancements.