mineral

Milky Quartz on Matrix

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: White/Opaque (Milky) with tan/grey host rock; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: White/Opaque (Milky) with tan/grey host rock
Luster: Vitreous to greasy

Identified May 31, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: White/Opaque (Milky) with tan/grey host rock; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed from hydrothermal solutions or cooling of silica-rich magma; commonly found in veins within igneous and metamorphic environments across all geological ages.

Uses & applications

Used in glassmaking, abrasives, silicon production for electronics, and as decorative specimens or metaphysical stones.

Geological facts

Milky quartz gets its cloudy appearance from tiny fluid or gas inclusions trapped during crystal growth. It is the most common variety of crystalline quartz found on Earth's crust.

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage. It is found globally; look for white veins in road cuts or mountain outcrops. It is extremely weather-resistant and often remains as pebbles in stream beds.

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