mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified May 24, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in hydrothermal veins or pegmatites as silicon-rich solutions cool and crystallize. It is one of the most common minerals found in the Earth's crust across all geological eras.

Uses & applications

Used in glass making, ceramics, as an abrasive, in construction as aggregate, and sometimes as a minor decorative stone or in landscaping.

Geological facts

The milky appearance is caused by tiny liquid or gas inclusions trapped during the crystal's growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its hardness (scratches glass), waxy luster, and lack of cleavage. Often found by searching gravel pits, mountain streams, and quartz veins in bedrock outcrops.