mineral

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (six-sided prisms meeting at a pyramid-shaped vertex); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glassy)

Identified March 31, 2026More mineral →

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Physical properties

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments through the cooling of silica-rich magma or from hydrothermal veins. It can be found in rocks from almost any geological age.

Uses & applications

Used in electronics (oscillators and pressure sensors), glassmaking, precision instruments, semi-precious 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. Pure quartz is perfectly clear; the 'rock crystal' name comes from the ancient Greek word 'krystallos', meaning 'ice', as they believed it was permanently frozen water.

Field identification & locations

Identify by its ability to scratch glass (hardness 7) and its lack of cleavage planes. Found globally, with famous deposits in Brazil, Arkansas (USA), and the Alps. Look for the distinct six-sided prism shape with striations horizontal across the crystal faces.

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