mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on the Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Indistinct; Specific gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Colorless and transparent
Luster: Vitreous (glass-like)

Identified March 25, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Colorless and transparent; Luster: Vitreous (glass-like); Crystal structure: Trigonal/Hexagonal; Cleavage: None/Indistinct; Specific gravity: 2.65.

Formation & geological history

Formed through the crystallization of magma or from hydrothermal veins. It can be found in a wide variety of geological environments and ages, ranging from Precambrian to more recent formations.

Uses & applications

Used in electronics (oscillators), manufacturing glass, jewelry (cabochons and beads), and widely popular in crystal healing and geological collections.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure clear quartz is often called 'Rock Crystal', a term derived from the Greek word 'krustallos' meaning ice.

Field identification & locations

Identify in the field by its 6-sided hexagonal prism shape ending in a pyramid, its inability to be scratched by steel, and the absence of cleavage planes. Common locations include Brazil, Arkansas (USA), and Madagascar.