mineral

Clear Quartz

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 20, 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 through the cooling of silica-rich magma or from hydrothermal veins. It occurs in a wide variety of geological environments ranging from igneous to metamorphic rocks across all geological ages.

Uses & applications

Used in electronics (piezoelectric properties), glassmaking, precision instruments, jewelry, and popular as a healing crystal or decorative collectible.

Geological facts

Quartz is one of the most abundant minerals in Earth's crust. 'Rock crystal' specifically refers to the clear, colorless variety. Ancient Greeks believed clear quartz was ice that had frozen so hard it would never melt.

Field identification & locations

Identify by its hardness (scratches glass), hexagonal crystal habit with horizontal striations on faces, and lack of cleavage. Found globally, with notable deposits in Brazil and Arkansas, USA.