mineral

Quartz (Crystal Cluster)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Colorless to white (milky); Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal system; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless to white (milky)
Luster: Vitreous (glassy)

Identified March 27, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. It is found in all geological ages and environments, predominantly in continental crust as a major component of igneous rocks like granite.

Uses & applications

Extensively used in the manufacture of glass and ceramics, as an abrasive in sandblasting, in electronics for its piezoelectric properties (oscillators), and as a popular semi-precious gemstone and collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the ancient Greeks believed quartz was ice that had frozen so hard it would never melt, hence the word 'krustallos' (ice).

Field identification & locations

Identify in the field by its hardness (it will scratch glass and steel), lack of cleavage, and characteristic hexagonal crystal points. It is found globally, with famous high-quality deposits in Arkansas (USA), Brazil, and the Alps.