mineral

Quartz crystal (likely milky/clear quartz)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; colorless to milky-white with glassy/vitreous luster and translucent edges. Trigonal crystal structure, no cleavage, and prominent conchoidal fracture; the specimen appears rough and possibly naturally broken or partly polished.

Identified September 16, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in cavities, veins, pegmatites, and hydrothermal systems; quartz is common from Precambrian rocks through modern deposits. Exact age and locality cannot be determined from the image.

Uses & applications

Used in glass, ceramics, abrasives, electronics, and timekeeping; clear attractive crystals are collected and sometimes cut as gemstones. This rough piece likely has modest decorative or educational value.

Geological facts

Quartz is one of Earth’s most abundant minerals and is the defining mineral of many veins and sandstones. Its lack of cleavage and conchoidal fracture help distinguish it from calcite and feldspar.

Field identification & locations

Look for glassy luster, hardness sufficient to scratch ordinary glass, and absence of cleavage; a streak test is white. Common worldwide, especially in Brazil, Arkansas, Madagascar, the Alps, and hydrothermal veins.