mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified July 6, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly in igneous rocks like granite or in hydrothermal veins. It crystallizes from silica-rich fluids over a broad range of temperatures and pressures throughout geological history.

Uses & applications

Extensively used in electronics (oscillators), optics, glassmaking, jewelry (as a gemstone), and as a popular metaphysical or decorative specimen.

Geological facts

Clear quartz is also known as Rock Crystal. The word 'crystal' comes from the Greek word 'krystallos', which means ice, as the ancients believed it was ice frozen so hard it would never melt.

Field identification & locations

Identified in the field by its hardness (scratches glass), glass-like appearance, and lack of cleavage. Found worldwide, with major deposits in Brazil and Arkansas, USA.