mineral

Milky quartz

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Typically white to translucent with a glassy-to-waxy luster and irregular fracture; Mohs hardness 7, no cleavage, hexagonal crystal structure, and specific gravity about 2.65. The cloudy appearance results from microscopic fluid inclusions or fractures.

Identified August 24, 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

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, and igneous or metamorphic rocks; specimens may range from ancient Precambrian material to recent hydrothermal deposits. The pictured piece is too weathered and small for precise identification or dating.

Uses & applications

Used for glass, ceramics, abrasives, foundry products, and engineered stone; attractive pieces are collected or used in inexpensive jewelry and décor. Common specimens generally have modest value.

Geological facts

Commonly confused with calcite or feldspar; quartz will not scratch easily with a steel knife, while calcite is much softer. It does not effervesce in dilute hydrochloric acid.

Field identification & locations

Common worldwide, including Brazil, Madagascar, the United States, and Alpine regions; identify by hardness, lack of cleavage, and conchoidal fracture. A scratch test and examination of crystal faces or inclusions can confirm it.