mineral

Milky Quartz

Silicon dioxide (SiO2)

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

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

Identified April 11, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to opaque; 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 solutions or gas-charged magmas. The milky appearance is caused by microscopic inclusions of fluids or gas trapped during the crystal's growth.

Uses & applications

Used in electronics as a frequency control, in quartz watches, for making glass and ceramics, as an abrasive, and frequently in jewelry or as decorative landscaping stone.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. While often overlooked by gem hunters, large veins of milky quartz are often indicators of gold deposits in geological prospecting.

Field identification & locations

Identify in the field by its white color, ability to scratch glass (Hardness 7), and its lack of cleavage, breaking instead in curved, shell-like patterns (conchoidal fracture). Found globally in variety of environments.