mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: White to off-white, opaque
Luster: Vitreous to greasy

Identified July 12, 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

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

Formation & geological history

Forms in wide variety of environments, most commonly in hydrothermal veins and pegmatites. The milky white color is caused by tiny gas or liquid inclusions trapped during crystal growth. Can be found in rocks of all geological ages.

Uses & applications

Used in glassmaking, as an abrasive, in the electronics industry (frequency control), and as a landscaping or decorative stone. Often used for spiritual or collecting purposes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The white 'milkiness' is actually due to microscopic fluid inclusions of gas, liquid, or both, trapped as the crystal formed millions of years ago.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and typical white opaque appearance. Found globally in riverbeds, mountains, and as garden stones. It is one of the most common rocks encountered by beginner collectors.