mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

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

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. They can grow in igneous, metamorphic, and sedimentary environments over millions of years.

Uses & applications

Used in electronics (oscillators), optical instruments, jewelry, glassmaking, and as a popular specimen for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz is often called 'Rock Crystal' and was once believed by ancient Greeks to be permanently frozen ice.

Field identification & locations

Identified by its hexagonal prism shape and ability to scratch glass. Found globally, with notable deposits in Brazil, Arkansas (USA), and Madagascar. Look for the characteristic 6-sided termination.