mineral

Clear Quartz

Silicon dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

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

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal structure: Trigonal; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Forms in a wide variety of geological environments, most notably through hydrothermal precipitation from silica-rich fluids and the cooling of igneous pegmatites. It is found in all eras of geological time.

Uses & applications

Extensively used in electronics for its piezoelectric properties, glassmaking, timekeeping (watches), and jewelry as a gemstone. It is also a staple for mineral collectors and decorative use.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz is often called 'Rock Crystal' and was believed by ancient Greeks to be ice that had frozen so hard it would never melt.

Field identification & locations

Identified in the field by its hardness (scratches glass), lack of cleavage, and transparent appearance. It is common worldwide in various rock types. Tumbled pieces are often heart-shaped or rounded through mechanical polishing.