mineral

Quartz / Quartz Geode fragment

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: Clear to milky white/tan
Luster: Vitreous (glassy)

Identified April 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in cavities within igneous or sedimentary rocks. This specific piece looks like a fragment of a small geode or a weathered crystalline nodule.

Uses & applications

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

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the German word 'Quarz', which has Slavic origins meaning 'hard'.

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage (it breaks in irregular, shell-like curves). Commonly found in riverbeds, mountains, and desert plains globally.

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