mineral

Blue Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, pale to deep blue color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Identified August 5, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, pale to deep blue color, vitreous to greasy luster, trigonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. The blue color is typically caused by microscopic inclusions of fibrous minerals like crocidolite or dumortierite, or due to Rayleigh scattering from lattice defects.

Uses & applications

Used primarily in lapidary arts, making tumbled stones, carvings, jewelry, and decorative items, as well as mineral specimen collecting.

Geological facts

Natural blue quartz is relatively rare compared to other varieties like amethyst or citrine. Many commercial blue quartz specimens on the market are actually dyed or heat-treated quartz.

Field identification & locations

Can be identified by its conchoidal fracture, lack of cleavage, hardness of 7, and characteristic blue coloration. Found worldwide, with notable deposits in Brazil, India, and the United States.