The chemical formula of mineral Azurite is indicated by Cu3(CO3)2(OH)2 or Copper Carbonate Hydroxide. Azurite is actually a Carbonate mineral. Azurite was first discovered in Chessy les Mines, France in the year 1824. Azurite owes its name from its azure-blue color. Both Azurite and azure are derived via Arabic from the Persian word lazhward, an area known for its deposits of another deep blue stone called lapis lazuli or stone of lazhward. Azurite was the most important pigment in the European painting during the Middle Ages and Renaissance. The European name of Azurite is Chessylite. Azurite is named after a famous Azurite locality in Chessy, France. Azurite is known to crystallize in the monoclinic system of crystal formation. In optical mineralogy, the monoclinic system of crystal formation comprises crystals having three axes of unequal lengths. Two of which are usually found in a position that is oblique or not perpendicular to one another. However, both of which are commonly found perpendicular to the third axis.
Azurite is a very popular mineral. Its popularity is brought about by its unparalleled deep blue color, azure. The deep blue color of Azurite mineral is due to the traces of copper contained in the chemical structure of the mineral and the way it chemically combines with the hydroxyls group (OH) and the carbonate groups (CO3). Copper is considered as a strong coloring agent. Azurite has been actually used as dye for paints and fabrics for eons. It is also used as jewelry, ornamental stone, pigmenting agent and is commonly considered as minor ore of copper. Azurite mineral is often found associated with the colorful mineral malachite, which is actually considered as its close cousin. It has close association with green malachite, which is found in many ways. They can occur together in one single specimen and they also have similar formula. It can be found that malachite can actually replace Azurite, which in effect makes a pseudomorph, or may be can actually produce an exact copy of Azurite crystal, which appear in shade of green instead of blue. Azurite is found to be chemically similar to the green malachite mineral. It usually occurs with green malachite, which may form green stains or specks commonly found on the Azurite crystals or aggregates. Azurite and malachite are usually found admixed or banded together forming the Azure-malachite, which is considerably attractive piece in the gem and mineral world.
Azurite is commonly considered as an unimportant ore of copper. This remains a fact even though the significance of Azurite mineral has been considered more impressive in the past. Azurite is only considered as a minor ore of copper, which is mostly because it is found usually associated with other more valuable ores of copper. A nice piece of combination commonly formed with malachite is usually found in fine crystal clusters, usually as nodular specimens, which are commonly considered interesting with fascinating microscope image. They are considered important piece of collection for any serious mineral collectors. It is because of the magnificent blue color of Azurite that makes the mineral a one-of-a-kind in the mineral world. Azurite is considered as one of those classic minerals. When this Azurite mineral is found mixed with dark red cuprite, it will result to a considerably rare mixture called ‘Bluebird’. These rare Bluebird, Azurite and Azure-malachite are all splendidly attractive and with significant hardness making them suitable for gem purposes. All these three minerals are fascinating and with exquisite microscope image under a gemological microscope.
Azurite mineral specimens, if mineral is found in small crystals or crusts, are commonly found in azure color or in deep blue or pale blue shades in transmitted light of petrographic polarizing microscope used optical mineralogy. There are Azurite specimens, which are found in too deep color when viewed with the aid of a polarizing light microscope for mineralogist. Azurite mineral specimen usually appear black under polarized light microscopes if found in larger crystals. There is natural Azurite found with malachite specimen that has a large vug filled with brilliant azurite crystals with very deep blue color that exhibits fascinating microscope image under a polarizing light microscope. Azurite is most commonly found showing a vitreous to dull luster when specimen is viewed in reflected light of petrographic polarizing light microscope. In optical mineralogy, vitreous luster is likened to the luster of a broken glass. Luster actually depends on the habit of the mineral. Some other specimens exhibit a sub-metallic luster when viewed in reflected light of polarizing microscope. Sub-metallic luster shows a slightly less than metallic reflectivity. Azurite is usually found showing cleavage between crossed nicols of polarized microscope used in optical mineralogy and it is usually in two directions. Azurite has good cleavage found in one direction and poor cleavage in the other direction. Azurite is commonly found exhibiting a conchoidal and sometimes splintery fracture when evaluated after several adjustments on the aperture diaphragm of the petrographic polarizing microscope used in optical mineralogy. In the field of optical mineralogy, chonchoidal fracture is described as a smooth curved fracture with concentric ridges of the type shown by glass. In optical mineralogy field of study, fracture describes how a mineral breaks when broken contrary to its natural cleavage planes. Azurite are commonly found brittle, a property generally displayed by glasses and most nonmetallic minerals. Azurite is most commonly found leaving a blue streak when specimen is rubbed on a white porcelain streak plate. There are no partings found and this Azurite is a rarely twinned mineral. The hardness measure of mineral Azurite when it is evaluated using the Mohs scale method is commonly found ranging 3.5 to 4.0. The specific gravity measure of Azurite gives an approximate value ranging from 3.7 grams per cubic centimeters to 3.9 grams per cubic centimeters, which is commonly considered heavier than average value.
Azurite crystals are commonly found in opaque appearance, but are translucent in thin splinters. They may also appear transparent if found in thin crystals. Crystal habit of Azurite as described in the field of optical mineralogy usually includes a typical tabular shape, which is commonly exhibiting a shape like that of a book. Azurite crystals may form as irregular blades with wedge shaped terminations, which are clearly visible when specimen is viewed with the aid of polarized microscopes used in optical mineralogy. Azurite also includes a short prismatic habit, where the dominant faces found are those of a prism when viewed under petrographic polarizing microscope. Sometimes they can be found in massive forms or in stalactitic habit. Stalactitic are shaped like pendant columns as stalactites or stalagmites. Small crystals of Azurite are usually found in prismatic, tabular, or equidimensional form. These crystals are frequently found striated between crossed nicols of polarizing light microscope for geologists. Other forms include crusty, earthy, as thin needles and in ball-like aggregates. They can sometime appear radiating, which exhibits elongate grains that radiate out from a center and fibrous, where individual grains are long slender fibers as well as columnar, which displays parallel arrangement of columnar grains. Azurite crystals are commonly not twinned. Some natural Azurite with malachite specimen appear to have one large deep vug commonly filled with brilliant azurite crystals with deep blue color, which exhibits an attractive and majestic microscope views in reflected light.
Azurite is easily distinguished by its blue color and streak, its reaction to cold, dilute hydrochloric acid, and is common association with malachite. Azurite mineral is chemically evaluated and found soluble in ammonia and it effervesces in nitric acid or it forms bubbles after the chemical reaction. Under ordinary conditions, Azurite mineral is commonly found stable. Azurite undergoes a chemical change in some localities. It loses some of its hydroxyl are the found altered to malachite but the crystal shape of original Azurite is only retained. There are times that only part of the Azurite mineral is found altered to malachite, while the other part remains as Azurite. When specimen is evaluated, it can be found that it is colored green on one end and blue on the other. This also has magnificent appearance when viewed with the aid of polarized light microscope. Azurite is highly demanded in the mineral world. It is very popular among serious mineral collectors because of its splendid bright blue color. Azurite minerals in bright blue crystals are usually cut into cabochons and beads, most especially the azure-malachite. Large masses of Azurite however, are sometimes cut and used as ornamental objects. Azurite is no longer used as blue pigmenting agent nowadays because in certain environments, Azurite alters to malachite and it blue color readily turns to green. Azurite is most commonly found exhibiting biaxial negative figure when viewed closely between crossed nicols of petrographic polarizing microscope. It also shows high surface relief when examined under several adjustments on the aperture diaphragm of the polarizing microscope for mineralogists. Azurite has relatively weak dispersion found exhibited when mineral is viewed with the aid of a polarizing light microscope. Pleochroism in blue color is also visible when the mineral is evaluated between crossed nicols of petrographic polarizing microscopes. There is no specific data on the toxicity and health dangers for mineral Azurite. However, these minerals should be treated with great care and use of sensible precautions is recommended upon handling them.
It is usually found associated with numerous other minerals such as malachite, calcite, cuprite, liroconite, aurichalcite, chrysocolla, cerussite, limonite, connellite, quartz, shattuckite, native copper, chalcopyrite and other oxidized copper. Azurite mineral commonly forms pseudomorphs over other minerals, usually retaining the original crystal shape of that mineral it pseudomorphed over. The best field indicators of Azurite mineral commonly include softness, color, crystal habits and its splendid association with other minerals. Azurite mineral as one of the mineral forms of copper is commonly found in oxidized zone in hydrothermal deposits. It can be found in numerous localities worldwide like Germany, England and France. Natural Azurite minerals can be found in the upper oxidized portions of copper ore deposits, which are often found near malachite, a green basic carbonate of copper. Azurite is also considered as a secondary mineral formed by the action of carbonated water acting on copper-containing minerals, or from copper containing solutions. The largest crystals to date have come from Tsumeb, Namibia, where many forms of this mineral exist. Special localities like Shaba, Congo, Lasal, Utah, New Mexico and Bisbee, Arizona in the United States, Tousitt, Morocco, and Mexico and in many localities in Europe. Good specimens have also come from Chessy, France, Burra Burra, South Australia and Broken Hill, New South Wales, Australia, Laurium, Greece and the Black Forest, Germany.
