mineral

Clear Quartz (Rock Crystal)

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 8, 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

Formed from silica-rich hydrothermal solutions or the cooling of magma in igneous rocks like granite. Common in veins and geodes. Can be found in rocks from nearly any geological age.

Uses & applications

Used in electronics (oscillators), glassmaking, abrasives, jewelry (as carvings or faceted stones), and by collectors for metaphysical or aesthetic purposes.

Geological facts

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

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage. Look for six-sided prisms ending in pyramids. Commonly found in mountainous regions worldwide, such as the Swiss Alps or Arkansas, USA.