mineral

Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white (milky); Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white (milky)
Luster: Vitreous (glassy) to greasy

Identified July 7, 2026More mineral →

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Physical properties

Formation & geological history

Forms in a wide variety of environments, most commonly by crystallizing from cooling magma or precipitating from hydrothermal veins. It is found in igneous, metamorphic, and sedimentary rocks across all geological ages.

Uses & applications

Used extensively in glassmaking, electronics (piezoelectric properties), abrasives, construction, and as gemstones or decorative specimens in jewelry and collecting.

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.

Field identification & locations

Identify by its ability to scratch glass and its lack of cleavage (it breaks with curved, shell-like surfaces). It is found globally; look for it in granite outcrops, riverbeds, or as veins in mountain ranges.