mineral

Blue Quartz

Quartz (Silicon Dioxide) with inclusions, SiO2

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Grayish-blue to deep blue; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65.

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

Identified July 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Grayish-blue to deep blue; Luster: Vitreous to waxy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65.

Formation & geological history

Formed in igneous and metamorphic environments. The blue color is typically caused by inclusions of other minerals like crocidolite, tourmaline, or dumortierite within the quartz matrix during crystallization.

Uses & applications

Primarily used as a decorative stone, in jewelry as cabochons or beads, and as a popular specimen for mineral collectors.

Geological facts

Unlike blue sapphire or topaz, the color in blue quartz is caused by the scattering of light by microscopic mineral inclusions, a phenomenon known as the Tyndall effect.

Field identification & locations

Identified by its signature waxy luster and blue-gray hue. It is commonly found in Brazil, India, and the United States (Virginia and North Carolina). Look for its characteristic lack of cleavage and hard, scratch-resistant surface.