mineral

Weathered quartz-rich stone, likely milky quartz

Quartz (SiO₂), possibly a quartz-rich metamorphic or igneous fragment

AI-generated identification · may be incorrect

White to pale gray, opaque, with a dull-to-glassy luster and irregular fracture; quartz hardness is Mohs 7, with no cleavage and typically hexagonal crystal structure. Dark lines and pits may be iron/manganese staining, inclusions, or surface weathering.

Identified September 3, 2026More mineral →

Explore Weathered quartz-rich stone, likely 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

Quartz crystallizes from silica-rich magma or hydrothermal fluids and also forms in metamorphic veins and quartzite; the specimen’s exact age and host rock cannot be determined from the image. Its rounded shape suggests natural stream or beach abrasion, or deliberate tumbling.

Uses & applications

Quartz is used in glass, ceramics, foundry materials, electronics, abrasives, and construction aggregate; attractive pieces are collected or used decoratively. This small, heavily weathered specimen has little commercial gemstone value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, producing an electrical charge when mechanically stressed. Milky quartz becomes opaque because of microscopic fluid inclusions and structural defects.

Field identification & locations

Test with a steel file or common glass: quartz should scratch glass and resist a steel blade. Common sources include quartz veins, granitic terrains, metamorphic rocks, river gravels, and beaches worldwide.