mineral

Milky Quartz

Silicon Dioxide (SiO2)

Mohs hardness: 7; Color: White to translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Hardness: 7
Color: White to translucent
Luster: Vitreous to greasy

Identified July 16, 2026More mineral →

Explore Milky Quartz in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Mohs hardness: 7; Color: White to translucent; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or as a constituent in igneous and metamorphic rocks. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glass manufacturing, electronics (quartz oscillators), abrasive materials, and as decorative stone or landscaping gravel.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by ancient civilizations for stone tools and carvings.

Field identification & locations

Identified in the field by its white color, hardness (will scratch glass), and lack of cleavage. Often found near granite outcrops or in stream beds as rounded pebbles.