Mineral

Quartz

Silicon Dioxide (SiO₂)

Hardness: 7 on the Mohs scale; Color: typically white, clear, or off-white/tan (milky quartz grade); Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Luster: Vitreous (glassy) to greasy

Identified March 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used extensively in the glass industry, electronics (piezoelectric properties), abrasives, and as a raw material for silicon-based products. Milky or common quartz is also used for landscaping, road construction gravel, and occasionally for lapidary work.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical and physical weathering, which is why it is the primary component of most beach sand and riverbed gravel.

Field identification & locations

Identify in the field by its hardness (it will easily scratch glass and stainless steel) and its lack of cleavage (it breaks into irregular, curved shards). This specimen appears to be 'Milky Quartz,' common in riverbeds and mountainous terrain worldwide.