mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 19, 2026More mineral →

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Physical properties

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

Formation & geological history

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

Uses & applications

Used as an abrasive, in glass making, electronics (piezoelectric properties), jewelry, and as a decorative stone in landscaping.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and white, opaque appearance. It is ubiquitous in mountainous and volcanic regions worldwide.