mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: White to cloudy
Luster: Vitreous (glassy) to greasy

Identified June 2, 2026More mineral →

Identify your own rocks.

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

App Store Google Play

Physical properties

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

Formation & geological history

Forms during the cooling of magma or by hydrothermal movement in veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in glassmaking, electronics (piezoelectric properties), abrasives, and as building aggregates. Also popular in gardening and jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz specifically gets its name from its white, opaque appearance which resembles milk.

Field identification & locations

Identify by its hardness (it can scratch glass and steel), lack of cleavage, and white opaque color. It is commonly found in gravel pits, riverbeds, and mountain ranges globally.