mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified April 1, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal solutions or cooling magma. Can be found in igneous, metamorphic, and sedimentary environments worldwide, often dating back hundreds of millions of years in various geological veins.

Uses & applications

Used in electronics (oscillators), optics, glassmaking, abrasives, jewelry (as semi-precious stones), and widely collected for 'healing' properties or aesthetic display.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as 'Rock Crystal' and was believed by Ancient Greeks to be permanently frozen ice.

Field identification & locations

Identify in the field by its hardness (will scratch glass but not be scratched by a steel knife) and its distinct conchoidal (shell-like) fracture pattern. To distinguish from glass, look for natural inclusions or double refraction.