mineral

Quartz Crystal

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear/transparent; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear/transparent
Luster: Vitreous (glassy)

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear/transparent; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Quartz forms through the cooling of silica-rich magma or from hydrothermal veins. It is found in igneous, metamorphic, and sedimentary environments across all geological ages.

Uses & applications

Used extensively in jewelry as gemstones, in electronics for its piezoelectric properties (watches, radios), in glassmaking, and as a popular collector specimen.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It was once believed by ancient Greeks to be ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its hardness (scratches glass), lack of cleavage, and hexagonal crystal habit. It is ubiquitous globally, especially in alpine crystals veins and granite pegmatites.