mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

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

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

Identified July 19, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous rocks like pegmatites, metamorphic rocks, and sedimentary environments via hydrothermal activity. It can precipitate from hot silica-rich solutions in veins.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), jewelry, gemstones, and as a popular specimen for mineral collectors.

Geological facts

Quartz is one of the most abundant minerals on Earth's crust. 'Rock crystal' comes from the Greek word 'krystallos,' meaning ice, as ancient Greeks believed it was permanently frozen water.

Field identification & locations

Identify by its six-sided prismatic shape, lack of cleavage (it fractures like glass), and its ability to scratch glass. Found worldwide, with major deposits in Brazil and Arkansas, USA.