Azurite is a soft, deep blue copper mineral produced by weathering of copper ore deposits. During the early 19th century, it was also known as chessylite, after the type locality at Chessy-les-Mines near Lyon, France.
The mineral has been known since ancient times, under the Greek name kuanos (κυανός: "deep blue", the root of English cyan) and the Latin name caeruleum. Since antiquity, azurite's exceptionally deep and clear blue has been associated with low-humidity desert and winter skies. The modern English name of the mineral reflects this association since both azurite and azure are derived via Arabic from the Persian lazhward, an area known for its deposits of another deep-blue stone, lapis lazuli ("stone of azure").
Azurite is a secondary mineral that usually forms when carbon-dioxide-laden waters descend into the Earth and react with subsurface copper ores. The carbonic acid of these waters dissolves small amounts of copper from the ore. The dissolved copper is transported with the water until it reaches a new geochemical environment. This new environment could be a location where water chemistry or temperature changes, or where evaporation occurs. If conditions are right, the mineral azurite might form. If these conditions persist for a long time, a significant accumulation of azurite might develop. This has occurred in many parts of the world.
Azurite precipitation occurs in pore spaces, fractures, and cavities of the subsurface rock. The resulting azurite is usually massive or nodular. In rare situations, azurite is found as stalactitic and botryoidal growths. Well-formed monoclinic crystals are infrequently found. These can only occur if azurite precipitates unrestricted in a fracture or cavity and is not disrupted by later crystallization of rock movements.
It is best known for its characteristic deep blue to violet-blue color. The blue color, known as "azure," is like the deep blue evening skies often seen above deserts and winter landscapes.
Azurite is not a common or abundant mineral, but it is beautiful and it's blue color attracts attention. It has been used by people in many parts of the world for thousands of years. Ancient people used it as an ore of copper, as a pigment, as a gemstone, and as an ornamental stone. It is still used for all of these purposes today.
Azurite is easy to cut and shape into cabochons, beads, small carvings, and ornaments. It also accepts a bright polish
In the United States, Arizona, New Mexico, and Utah are the notable locations for finding azurite. More important deposits have been found in France and Namibia. Noteworthy occurrences have been found in Mexico, Chile, Australia, Russia, and Morocco.