mineral

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on the Mohs scale; Color: Colorless to white/cloudy; Luster: Vitreous (glassy) to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on the Mohs scale
Color: Colorless to white/cloudy
Luster: Vitreous (glassy) to greasy

Identified March 1, 2026More mineral →

Explore Quartz (Milky or Cloudy Quartz) in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. It is found in all types of geological environments (igneous, metamorphic, and sedimentary) and can be over a billion years old in some crustal formations.

Uses & applications

Used widely in glassmaking, electronics (piezoelectric properties), abrasives, and as a component in concrete and mortar. Higher quality specimens are used for semi-precious jewelry and metaphysical collecting.

Geological facts

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

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its waxy or glassy luster. It is found globally, often appearing as veins in darker rock or as smooth pebbles in riverbeds. Collectors should look for distinct crystal faces for higher value.