mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous

Identified May 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide range of geological environments, most commonly from the cooling of magma in igneous rocks like granite or from hydrothermal veins. It can be found in rocks of all ages.

Uses & applications

Extremely versatile; used in electronics (oscillators), optical instruments, glassmaking, abrasive blasting, and extensively in jewelry and gemstone carving.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The name 'quartz' comes from the German word 'Quarz', while 'crystal' comes from the Greek word 'krystallos', meaning ice.

Field identification & locations

Identified by its transparency, its ability to scratch glass (hardness 7), and its lack of cleavage. Look for it in riverbeds, mountain veins, or within geodes. Collectors value specimens with high clarity or unique inclusions.