mineral

Quartz (Milky/Crystal variety)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: White to translucent (milky). Luster: Vitreous (glassy) to greasy. Crystal structure: Trigonal/Hexagonal. Cleavage: Indistinct (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: White to translucent (milky)
Luster: Vitreous (glassy) to greasy

Identified March 8, 2026More mineral →

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Physical properties

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. Typically crystallizes from silica-rich hydrothermal fluids or within magma cooling at depth. These specimens appear to be river-worn or glacially transported cobbles.

Uses & applications

Used widely in glassmaking, electronics (piezoelectric properties), abrasives, and as decorative gravel or landscaping stone. Higher quality crystals are used in jewelry and holistic healing practices.

Geological facts

Quartz is the second most abundant mineral in Earth's crust. It is extremely chemically and physically stable, which is why it remains as pebbles long after other minerals have weathered away.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage. Look for a glassy luster and hexagonal crystal faces if not tumbled. Commonly found in riverbeds, gravel pits, and mountain ranges globally.

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