Lazulite is a mineral with a hardness of 6 out of 10 on the Mohs scale of mineral hardness [?]. These Monoclinicly structured gems are made of magnesium aluminum hydroxyphosphate, their full chemical compound being MgAl2(PO4)2(OH)2.

Lazulite is a compact, pleochroitic mineral which forms a series to scorzalite. It is dichroic, with a monoclinic crystal system.

It appears as pointed, pseudo-dipyramidal, bright blue crystals in microgranular masses. It is hard, medium heavy, fragile with indistinct prismatic cleavage. It is translucent, with vitreous luster. It is infusible, discolors and breaks into small fragments when heated. It dissolves with diffulty in strong hot acids.

It is a deep blue mineral, and has refractive indices in the range of tourmaline with a higher birefringence. Its pleochroism ranges strong from colorless to blue and deep blue.

Under LWUV (long wave ultraviolet) light it shows spots or streaks of an orange or copper-red. Pinkish under SWUV (short wave ultraviolet light). Yellowish glow under X-rays. Sometimes whitish fluorescence under SWUV.

Lazulite occurs in hypersilicic rocks, igneous (pegmatites, quartz veins), where it is associated with andalusite and rutile, or in metamorphic rocks (quartzites), where it occurs with quartz, corundum, kyanite, sillimanite, garnet, and sapphirine.

Beautiful crystals up to 2 inches long were found in the quartzites of Grave Mountain (Georgia, USA); at Zermatt (Switzerland), Werfen and Vorai (Austria); and Horrsjoberg (Sweden). Scorzalite, the iron analog of lazulite, is found mainly in pegmatites in Brazil.

Fine blue transparent lazulite may resemble Paraiba tourmaline, this material originating probably from west of Dattas, Minas Gerais, Brazil. Fine green material is also found in the Chilas area of the northern areas of Pakistan, and Angola is another possible source.

A variety of lazulite is called berkeyite - a blue, transparent gem quality variety of lazulite from Brazil.

Other names for lazulite include azure spar, blue spar, and klaprothine.

Misnomers for lazulite include blue opal, false lapis, and false lapis lazuli.

Lazulite is not to be confused with lazurite.

The specific gravity [?] for Lazulite is 3.1, it's refractive index [?] is 1.61-1.64, and it's double refraction [?] is 0.031.

History

Lazulite derives its name from the Arabic word meaning "heaven," or the German "lazurstein" meaning "blue stone," in reference to its colour.It was first described in 1795 for deposits from Styria, Austria.

Industrial Usages

Lazulite is used as ornamental article and seldom cut as gemstone. It is an attractive ornamental stone of minor importance.

You May Also Like...

Lapis Lazuli

Lapis Lazuli: Lapis lazuli is composed of several minerals in small quantities - augite, calcite, diopside, mica, hauynite, hornblende, pyrite. Because of this some experts consider it a rock, more than a mineral. The main ingredient of Lapis lazuli is Lazurite. It has a uniform, massive, or sometimes granular appearance, with fairly distinct crystals. It is semi-opaque to opaque, with a surface that can take (read full)

Sodalite

Sodalite: Sodalite is a sodium aluminum silicate chloride in the Sodalite group with an isometric crystal system. Its royal blue forms are the best known. As a mineral, it is a principal component of lapis lazuli. It appears very rare as dodecahedrons, crystals with 12 faces, but usually it shows as compact masses, bright blue, white or gray with green tints. It is unsaturated and rarely appears with inclu (read full)

Tags

Terms

Double Refraction or dr is the ability of a mineral to separate a refracted ray of light into 2 rays. If held over an image or text it will display the object 2x its original size.

Mohs Scale of Mineral Hardness is the standard used to categorize a mineral's ability to resist scratching. It gets its name from Friedrich Mohs, the German geologist who first created the scale.

RI or Refractive Index defines light's ability to move through the mineral or in a general sense, any material.

SG or Specific Gravity is the ratio of the weight of any substance to that of pure water at temperature of 3.98°C(39.2°F) and standard atmospheric pressure. This is important to note when actively seeking these minerals in the wild. Minerals with a higher SG will settle below material with a lower sg over time.