mineral

Quartz (Clear Quartz / Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale. Color: Colorless and transparent. Luster: Vitreous (glassy). Crystal system: Trigonal/Hexagonal. Cleavage: Poor/None, conchoidal fracture. Specific gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glassy)

Identified July 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: Colorless and transparent. Luster: Vitreous (glassy). Crystal system: Trigonal/Hexagonal. Cleavage: Poor/None, conchoidal fracture. Specific gravity: 2.65.

Formation & geological history

Forms in a wide variety of geological environments including igneous, metamorphic, and sedimentary rocks. Typically crystallizes from cooling magma, hydrothermal fluids, or pegmatites.

Uses & applications

Used in jewelry, gemstone carvings, electronics (piezoelectric oscillators), optics, glass manufacturing, and highly popular among mineral collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed clear quartz was ice frozen so hard that it would never melt, calling it 'krystallos'.

Field identification & locations

Identified by its ability to scratch glass (hardness 7), glassy luster, lack of distinct cleavage, and conchoidal fracture. Commonly found worldwide in granites, pegmatites, quartzites, and stream gravels.