mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 28, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms through the crystallization of silica-rich magma or hydrothermal fluids in veins. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth. Significant deposits range from Precambrian to recent geological ages.

Uses & applications

Used in glass making, abrasive blasting, electronics (due to piezoelectric properties), and as decorative base material in landscaping and jewelry. Small tumbled pieces are popular in the metaphysical and collecting communities.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many cultures to produce stone tools due to its hardness and sharp edges when fractured.

Field identification & locations

Identified in the field by its white color, inability to be scratched by a steel knife, and its lack of cleavage. Commonly found in riverbeds, mountain ridges, and as veins within granite or schist. Avoid confusion with white calcite by testing with acid; quartz will not fizz.