mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Colorless to transparent
Luster: Vitreous

Identified June 11, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments. Most clear crystals form in hydrothermal veins or pegmatites as magma cools and silica-rich fluids crystallize.

Uses & applications

Used in glassmaking, electronics (quartz oscillators), jewelry, and as a popular specimen for mineral collectors and metaphysical practices.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and hexagonal crystal habit. Found globally, with major deposits in Brazil and Arkansas, USA.