mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct (conchoidal fracture); Specific Gravity: 2.65

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

Identified July 18, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in all types of environments (igneous, metamorphic, and sedimentary) but most commonly crystallizes from magma or in hydrothermal veins. It is one of the most abundant minerals in the Earth's crust.

Uses & applications

Used in electronics (oscillators), optical instruments, glass manufacturing, abrasives, and extensively in jewelry and gemstone collecting.

Geological facts

Quartz is piezoelectric, meaning it generates an electric charge in response to applied mechanical stress, which is why it is used in watches and clocks. Clear colorless quartz is also known as 'Rock Crystal'.

Field identification & locations

Identify by its ability to scratch glass, its glassy luster, and characteristic conchoidal (shell-like) fractures. It is found worldwide, with major high-quality deposits in Brazil and Arkansas, USA.