mineral

Clear Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glass-like); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless/Transparent
Luster: Vitreous (glass-like)

Identified July 12, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glass-like); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in a wide variety of environments, most commonly from the cooling of magma (igneous) or from hydrothermal veins. It is one of the most abundant minerals in the Earth's crust and can be found in rocks of all ages.

Uses & applications

Widely used in electronics for its piezoelectric properties (watches, radios), in glassmaking, as an abrasive, and extensively in jewelry and gemstone collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is known as rock crystal. The name comes from the Greek word 'krustallos', meaning ice, because the ancients believed it was ice frozen so hard it would never melt.

Field identification & locations

Identify by its hardness (will scratch glass), lack of cleavage, and transparent glass-like appearance. It is found globally, with significant deposits in Brazil, Arkansas (USA), and Madagascar. Look for the characteristic six-sided prism shape in the field.