mineral

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on the Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glass-like); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glass-like)

Identified February 5, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glass-like); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly from the cooling of magma in igneous rocks like granite, or through hydrothermal veins. It is found in geological formations of all ages, from Precambrian to recent times.

Uses & applications

Extensively used in jewelry (faceting and beads), electronics (as oscillators due to piezoelectric properties), glassmaking, and abrasive industrial applications. It is also highly prized by metaphysical collectors.

Geological facts

Clear quartz is known as the 'Universal Crystal' and has been used since antiquity for tools and ceremonial objects. The name 'quartz' comes from the Greek word 'krustallos', meaning ice, as ancients believed it was ice that had stayed permanently frozen.

Field identification & locations

Identify in the field by its ability to scratch glass, its hexagonal crystal habit (if not tumbled), and its lack of cleavage. Look for it in riverbeds, quartz veins in mountain ranges, and within granitic outcrops. It is found globally, with major deposits in Brazil and Arkansas, USA.

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