mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 11, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins or as a late-stage crystallizing mineral in igneous rocks like granite. Its milky appearance is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, abrasives, electronics (piezoelectric properties), and as decorative stone or landscaping material.

Geological facts

Quartz is one of the most abundant minerals in the Earth's crust. The 'milky' look is specifically due to tiny bubbles of water or CO2 that scatter light within the crystal.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and characteristic waxy/glassy luster. It is found globally in almost all geological environments including mountains, beaches, and riverbeds.