mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (often found as 6-sided prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

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

Identified March 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal solutions or the cooling of magma in igneous rocks; can also occur in sedimentary and metamorphic environments. It precipitates in cavities and veins across all geological ages.

Uses & applications

Used in jewelry (pendants, beads), glassmaking, electronics (piezoelectric oscillators), abrasives, and as a popular metaphysical or decorative collector's stone.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the term 'crystal' comes from the Greek word 'krustallos', meaning ice, as ancients believed it was permanently frozen water.

Field identification & locations

Identify by its 6-sided crystal habit, hardness (will scratch glass and steel), and lack of cleavage. Common locations include Brazil, Madagascar, and Arkansas (USA). For collectors, look for high transparency and terminations (pointed ends).