mineral

Clear quartz crystal

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; colorless to milky with vitreous luster, translucent clarity, conchoidal fracture, and typically hexagonal prismatic crystal structure. The specimen appears natural and partly cloudy, with internal fractures and possible iron-oxide staining.

Identified August 20, 2026More mineral →

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Physical properties

Formation & geological history

Quartz crystallizes from silica-rich hydrothermal fluids, pegmatites, and cavities in igneous or metamorphic rocks; individual crystals may range from ancient Precambrian to geologically recent. This piece is likely a vein or cavity-grown crystal rather than a distinct rock type.

Uses & applications

Used in glass, electronics, watches, abrasives, and engineered stone; clear crystals are collected and occasionally cut as gemstones. Its value is mainly aesthetic unless exceptionally clear, large, or well-formed.

Geological facts

Quartz is the second-most abundant mineral in Earth’s continental crust and exhibits piezoelectricity. The visible cloudy zones commonly result from fluid inclusions, fractures, or microscopic mineral impurities.

Field identification & locations

Identify by hardness, glassy luster, lack of cleavage, and six-sided crystal faces; it should scratch ordinary glass but not be scratched by a steel knife. Common sources include Brazil, Madagascar, Arkansas, the Alps, and many hydrothermal veins worldwide.