mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

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

Hardness: 7 on Mohs scale
Color: Clear to translucent white
Luster: Vitreous (glassy)

Identified March 16, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide variety of environments including igneous (granite/pegmatites), metamorphic (quartzite), and sedimentary rocks. It crystallizes from silica-rich hydrothermal vents, cooling magma, or precipitation from solutions. Occurs across all geological ages from Archean to recent.

Uses & applications

Extensively used in electronics for its piezoelectric properties (watches, radios), glass manufacturing, abrasives, construction sand, and widely in jewelry/gemstone collecting and alternative medicine (crystal healing).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name is derived from the German word 'Quarz', which likely stems from a Slavic word meaning 'hard'. It is used to define the hardness of 7 on the Mohs scale.

Field identification & locations

Identify in the field by its ability to scratch glass (hardness >5.5) and its lack of cleavage (it breaks in curved 'conchoidal' patterns like glass). Found globally in mountain ranges, riverbeds, and as a primary component of beaches. It is a common 'seeker' mineral for gold prospectors.