mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

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

Identified April 23, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or through hydrothermal activity in veins. It is found in a wide variety of geological environments ranging from igneous to metamorphic and sedimentary rocks.

Uses & applications

Used in electronics (oscillators), optical instruments, jewelry, glass manufacturing, and as a popular collector's specimen for 'metaphysical' and aesthetic purposes.

Geological facts

Quartz is one of the most abundant minerals in the Earth's crust. 'Rock Crystal' comes from the Greek word 'krystallos', meaning ice, as ancient Greeks believed it was permanently frozen ice.

Field identification & locations

Identify by its ability to scratch glass, its colorless transparency, and its characteristic shell-like (conchoidal) fracture. Commonly found in pegmatites, river beds, and mountainous regions worldwide.