mineral

Raw quartz specimen (likely milky or smoky quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent gray-white to smoky gray, with vitreous luster and irregular/conchoidal fracture. Quartz is trigonal and lacks cleavage; the specimen appears as a rough, fractured aggregate rather than distinct crystals.

Identified September 5, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, and igneous or metamorphic rocks. Quartz is common from Precambrian rocks through modern hydrothermal deposits; the dark tint may reflect inclusions or irradiation-related color centers.

Uses & applications

Used in glass, ceramics, electronics, abrasives, and engineered stone; clear varieties are cut as gemstones. This rough piece is mainly suitable for collecting or educational display.

Geological facts

Quartz is one of Earth’s most abundant minerals and is piezoelectric, producing an electrical charge under pressure.

Field identification & locations

Identify by its glassy luster, lack of cleavage, hardness that can scratch ordinary glass, and typically pale streak. Common worldwide, especially in Brazil, Madagascar, the United States, and Alpine-type veins.