Azurite can be easily identified by its unique azure blue color, although its color does closely resemble that of lapis lazuli, but it lacks speckles of golden pyrite (fool’s gold). Azurite is frequently found mixed with malachite; hybrid malachite and azurite specimens are known in the trade as ‘azure-malachite’ or sometimes without the hyphen, as ‘azurmalachite’.
Other azurite hybrid varieties exist as well, including a rare cuprite mix known as ‘bluebird’ in the gem trade. However, through simple testing, each of these gems are easily distinguished from azurite. Other gems that can cause confusion are sodalite, lazurite, dumortiertite and hauynite, but azurite’s color is very unique and through close inspection, all similar gems can be distinguished with basic tests.
Azurite Origin and Gemstone Sources
Azurite is found in many locations in the world. The most important origins include Utah, Arizona and New Mexico (USA). Other sources include Mexico, Namibia, Congo, Morocco, France and Australia. One of the first major sources of azurite was in Chessy, a small commune in the eastern suburbs of France.
Buying Azurite and Determining Azurite Gemstone Value
Azurite is famed for its vivid blue color. The name ‘azure blue’ refers to the deep lapis lazuli blue color that can be seen in azurite. Azurite is often found mixed with green malachite and these will have mix of blue and green color.
Azurite Clarity and Luster
Azurite most often occurs opaque in clarity. When cut and polished, it has a very appealing vitreous luster, much like malachite. Transparent and translucent specimens are rare but do exist.
Azurite Cut and Shape
Azurite today is mainly a collector’s stone. It is very rare and when it is found in gemstone quality, it will usually be cut en cabochon. It is also often used for ornamental objects and gemstone carvings. It is only rarely faceted. Azurite is sometimes traded as beads or tumbled stones, but since azurite is relatively soft, it is not ideal for beaded jewelry. Azure-malachite is more common than pure azurite, and is almost always cut en cabochon, or offered as tumbled stones and beads.
Azurite is not typically treated. There are no known official or approved enhancements. Some specimens may be coated with a colorless wax to improve luster. Coating is not a common practice and should be disclosed by the seller.
Azurite Gemological Properties:
Chemical Formula: Cu3(CO3) 2(OH)2
Crystal Structure: Monoclinic; short columnar, dense aggregates
Color: Dark-blue, azure blue
Hardness: 3.4 to 4 on the Mohs scale
Refractive Index: 1.720 to 1.848
Density: 3.70 to 3.90
Transparency: Transparent to opaque
Double Refraction / Birefringence: 0.108 to 0.110