mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless/Transparent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal (often small conchoidal fragments); Cleavage: None (indistinct); Specific Gravity: 2.65.

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

Identified March 21, 2026More mineral →

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Physical properties

Formation & geological history

Formed through the cooling and crystallization of silica-rich magma or from hydrothermal solutions in veins and cavities. Can be found in rocks from virtually any geological age.

Uses & applications

Used in electronics for its piezoelectric properties, glassmaking, abrasives, and extensively in jewelry and gemstone collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Historically, the ancient Greeks believed clear quartz was fossilized ice that would never melt.

Field identification & locations

Identify in the field by its hardness (will scratch glass), glassy luster, and lack of cleavage. Commonly found in riverbeds, mountains, and as crystals inside geodes globally.