mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

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

Identified March 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or precipitation from hydrothermal veins. Found in various geological environments spanning from Precambrian to the present day.

Uses & applications

Used in the gemstone industry for carvings (like the pineapple shown), high-end jewelry, and crystal healing collections. Industrially used in optics, electronics (as oscillators), and glassmaking.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, it was believed by ancient Greeks to be ice that had frozen so hard it would never melt, hence the name 'krystallos'.

Field identification & locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and hexagonal prism habit. Common locations include Brazil, Madagascar, and the United States (Arkansas). Collectors look for clarity and unique inclusions.