mineral

Quartz (Milk or Clear)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless to white/cloudy
Luster: Vitreous (glassy)

Identified June 7, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich magma cooling in igneous rocks or precipitated from hydrothermal veins. Found in various geological ages ranging from billions of years old to recent formations.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), construction (as sand/gravel), and as a gemstone or specimen for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Its name comes from the Greek word 'krystallos', meaning ice, as the Greeks believed it was permanently frozen ice.

Field identification & locations

Identify by its hardness (it can scratch glass and steel) and lack of cleavage (it breaks in curved shell-like patterns). Found worldwide in mountain ranges, riverbeds, and beaches.