mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: White to Off-white (milky); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 Mohs
Color: White to Off-white (milky)
Luster: Vitreous to greasy

Identified June 13, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 Mohs; Color: White to Off-white (milky); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Forms through hydrothermal activity where silica-rich fluids cool in veins or crustal pockets. It can be found across all geological ages, often in metamorphic or igneous terrains.

Uses & applications

Used in glass manufacturing, as an abrasive, in electronics for its piezoelectric properties, and as decorative landscaping stone or crystal healing specimens.

Geological facts

The 'milky' appearance is caused by millions of tiny microscopic inclusions of gas or liquid trapped during crystal growth. Quartz is the second most abundant mineral in the Earth's continental crust.

Field identification & locations

Identify by its hardness (scratches glass), white color, and lack of cleavage. Often found in quartz veins in mountainous regions or as river-worn cobbles.