mineral

Milky Quartz

Silicon dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: Opaque white to translucent
Luster: Vitreous to greasy

Identified July 19, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Opaque white to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a constituent in igneous, metamorphic, and sedimentary rocks. The milky appearance is caused by tiny fluid or gas inclusions trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, silicon production for electronics, construction aggregate, and frequently as decorative landscaping stones or tumbled pocket stones.

Geological facts

Milky quartz is the most common variety of crystalline quartz. It is often found associated with gold in hydrothermal vein deposits, leading to it being a primary target for prospectors.

Field identification & locations

Can be identified by its ability to scratch glass and lack of cleavage. Look for it in riverbeds, mountain outcrops, and glacial till. It is ubiquitous worldwide.