mineral

Clear Quartz

Silicon Dioxide (SiO2)

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

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

Identified March 15, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich magma or via hydrothermal activity in veins. It can occur in nearly all geological environments and across all geological ages, often as the last mineral to crystallize in igneous rocks.

Uses & applications

Widely used in jewelry (as Rock Crystal), glassmaking, electronics (piezoelectric properties for oscillators), ceramics, and as a popular specimen for gemstone collectors and metaphysical enthusiasts.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Famous specimens include giant geodes found in Brazil. It has been used since antiquity for 'crystal balls' and hardstone carving.

Field identification & locations

Field identification: It will scratch glass, has no cleavage (breaks like glass), and is insoluble in most acids. Commonly found in riverbeds, mountain ranges, and pegmatites worldwide (notably Brazil, Arkansas, and Madagascar).