mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (prism with pyramidal ends); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 (Mohs scale)
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified June 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the crystallization of molten magma or from hydrothermal veins. It can occur in nearly every geological environment and is found in all three rock types (igneous, sedimentary, and metamorphic).

Uses & applications

Used in glassmaking, gemstone jewelry, precision electronics (piezoelectric properties for oscillators), ceramics, and as a popular metaphysical or decorative specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz is known as 'Rock Crystal' and has been used for carving crystal balls and cameos since antiquity.

Field identification & locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and vertical striations on crystal faces. It is commonly found in Arkansas (USA), Brazil, and the Alps.