mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Colorless to transparent with minor iron staining at the tip. Luster: Vitreous (glassy). Crystal Structure: Hexagonal (trigonal prismatic). Cleavage: None (conchoidal fracture). Specific Gravity: ~2.65.

Hardness: 7 on Mohs scale
Color: Colorless to transparent with minor iron staining at the tip
Luster: Vitreous (glassy)

Identified July 27, 2026More mineral →

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Physical properties

Formation & geological history

Forms during late-stage crystallization of igneous rocks (pegmatites), in hydrothermally active veins, and metamorphic environment under varying temperatures and pressures.

Uses & applications

Used extensively in gemstone jewelry, ornamental carvings, electronics (piezoelectric applications), glass manufacturing, and crystal collection.

Geological facts

Clear quartz is one of the most abundant minerals in Earth's continental crust. In ancient times, people believed it was permanently frozen ice created by the gods.

Field identification & locations

Identified by its hexagonal crystal habit, hardness (scratches glass readily), conchoidal fracture, and glassy transparency. Found globally in quartz veins and pegmatites, with notable locations in Brazil, Arkansas (USA), and the Alps.