mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Colorless/Transparent
Luster: Vitreous (glass-like)

Identified March 27, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Colorless/Transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed from the crystallization of molten magma or through hydrothermal activity in veins. Quartz is found in igneous, metamorphic, and sedimentary rocks of all geological ages from the Archean to the Cenozoic.

Uses & applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction as an abrasive, and extensively in jewelry and gemstone collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure transparent quartz is often called 'Rock Crystal' and was believed by the ancient Greeks to be ice that had frozen so hard it would never melt.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and transparent appearance. It is found globally, notably in Brazil, Madagascar, and Arkansas, USA. Collectors look for clarity and well-defined crystal faces.