mineral

Clear Quartz

Silicon Dioxide (SiO2)

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

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

Identified July 12, 2026More mineral →

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Physical properties

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

Formation & geological history

Forms in a wide variety of environments, most commonly by crystallizing from cooling magma or precipitating from hydrothermal veins. It is found in all three major rock types (igneous, sedimentary, and metamorphic).

Uses & applications

Extensively used in electronics for its piezoelectric properties (watches, radios), as an abrasive in sandblasting, in glassmaking, and widely in jewelry and crystal healing collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Ancient Greeks believed quartz was ice that had frozen so hard it would never melt, which is why they called it 'krystallos'.

Field identification & locations

Identify by its ability to scratch glass (hardness 7), lack of cleavage, and glassy appearance. Common in granite outcroppings and as pebbles in riverbeds worldwide.