mineral
Milky quartz
Quartz (silicon dioxide, SiO₂)
AI-generated identification · may be incorrectTypically white to translucent with a vitreous-to-waxy luster and no cleavage; Mohs hardness 7, conchoidal fracture, hexagonal crystal structure, and specific gravity about 2.65. The specimen appears rough and possibly partly weathered or coated, so visual identification is provisional.
Identified More mineral →
Explore Milky quartz in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Typically white to translucent with a vitreous-to-waxy luster and no cleavage; Mohs hardness 7, conchoidal fracture, hexagonal crystal structure, and specific gravity about 2.65. The specimen appears rough and possibly partly weathered or coated, so visual identification is provisional.
Formation & geological history
Forms when silica-rich fluids crystallize in veins, cavities, and igneous or metamorphic rocks; quartz is common from Precambrian through modern geological settings. Its cloudy appearance results from microscopic fluid inclusions, fractures, or mineral impurities.
Uses & applications
Used extensively in glass, ceramics, foundry materials, abrasives, electronics, and engineered stone; attractive pieces are sold as inexpensive mineral specimens or cabochons.
Geological facts
Quartz is one of Earth’s most abundant minerals and is the defining component of many quartz veins and quartz-rich rocks. It commonly occurs with feldspar, mica, calcite, and sulfide minerals.
Field identification & locations
Test by scratching glass or steel (quartz should scratch glass), while a steel knife should not scratch it; inspect for conchoidal fracture and lack of cleavage. Common worldwide, especially in Brazil, Madagascar, the Alps, and quartz-vein districts.
