mineral

Blue Quartz

Silicon Dioxide (SiO2) with inclusions

Hardness: 7 on Mohs scale; Color: Grayish-blue to deep blue; Luster: Vitreous (glassy) to waxy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Grayish-blue to deep blue
Luster: Vitreous (glassy) to waxy

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Grayish-blue to deep blue; Luster: Vitreous (glassy) to waxy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Forms in igneous and metamorphic environments. The blue color is typically caused by Rayleigh scattering from microscopic inclusions of minerals like crocidolite, tourmaline, or rutile within the quartz matrix.

Uses & applications

Primarily used as a decorative stone, in lapidary work for cabochons and beads, and for metaphysical collecting.

Geological facts

Unlike sapphire or lapis lazuli, blue quartz is rarely a vibrant blue; it usually has a smoky or denim-like hue. It is often found in the Blue Ridge Mountains of the United States.

Field identification & locations

Identify by its hardness (will scratch glass) and lack of cleavage. Look for the characteristic waxy to glassy luster and conchoidal fracture patterns on broken edges. Commonly found in Virginia, USA, and Brazil.