mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Colorless/Transparent; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless/Transparent
Luster: Vitreous

Identified May 1, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Colorless/Transparent; Luster: Vitreous; Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Forms from the cooling of silica-rich magma or from hydrothermal veins. It can be found in igneous, metamorphic, and sedimentary environments. Many specimens date back millions of years to the Cenozoic or Mesozoic eras.

Uses & applications

Used in electronics (as oscillators), glass manufacturing, abrasives, jewelry, and as a popular focus in crystal healing and geological collections.

Geological facts

Quartz is one of the most abundant minerals on Earth. Its name comes from the German word 'quarz', which originally meant 'hard'. Piezoelectric properties allow it to generate an electrical charge under mechanical stress.

Field identification & locations

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