mineral

Quartz crystal

Quartz (silicon dioxide, SiO₂), possibly milky quartz

AI-generated identification · may be incorrect

Typically Mohs hardness 7, white to translucent, with a vitreous luster and hexagonal crystal structure; lacks cleavage and shows conchoidal fracture. The specimen appears roughly cubic from breakage or cleavage-like surfaces, so identification is somewhat uncertain from the image.

Identified August 11, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich hydrothermal fluids, igneous melts, and metamorphic veins over a broad range of geological ages. Common settings include granitic pegmatites, quartz veins, and sedimentary cavities.

Uses & applications

Used in glassmaking, electronics, abrasives, ceramics, and construction; clear crystals are collected or used as gemstones. This small rough piece has little commercial value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, producing an electrical charge when mechanically stressed. Milky color results from microscopic fluid inclusions or fractures.

Field identification & locations

Identify by its glassy luster, lack of cleavage, hardness greater than ordinary glass, and conchoidal fracture; a scratch test should be used cautiously. Common worldwide, especially in Brazil, Madagascar, the United States, and quartz-vein districts.