mineral

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous (glass-like), Crystal Structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Identified March 15, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale), Color: Colorless/Transparent, Luster: Vitreous (glass-like), Crystal Structure: Trigonal (hexagonal prisms), Cleavage: None (conchoidal fracture), Specific Gravity: 2.65

Formation & geological history

Forms in igneous, metamorphic, and sedimentary rocks. Most commonly crystallizes from cooling magma or hydrothermal veins. Age can range from millions to over a billion years depending on the host rock formation.

Uses & applications

Used in electronics for its piezoelectric properties (watches, radios), high-end glass manufacturing, jewelry facets, and as a popular specimen for gemstone collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as 'rock crystal'. Ancient Romans believed quartz was permanently frozen ice because it was found near glaciers.

Field identification & locations

Identify in the field by its hexagonal (six-sided) crystal habit and its ability to scratch glass. Found globally, with massive deposits in Brazil, Arkansas (USA), and Madagascar. Collectors look for terminated points and clarity.