mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to translucent
Luster: Vitreous (glassy) to greasy

Identified March 21, 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: Opaque white to translucent; Luster: Vitreous (glassy) to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich hydrothermal veins or within igneous pegmatites. The milky white color is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can be found in geological formations spanning from prehistoric eras to relatively recent deposits.

Uses & applications

Used in glass manufacturing, as an abrasive, and in the production of silicon for electronics. In jewelry, it is often used for beads or cabochons. It is also a popular specimen for beginner rock collectors due to its abundance.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. Legend in some cultures suggests that quartz is 'eternal ice' that has frozen so hard it can no longer melt.

Field identification & locations

Identify in the field by its ability to scratch glass (hardness test), its lack of cleavage, and its characteristic waxy or glassy luster. Often found in riverbeds, mountains, and soil as float. It serves as an indicator mineral for potential gold veins in certain geological settings.