mineral

Clear Quartz Geode

Crystalline Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white; Luster: Vitreous/glassy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white
Luster: Vitreous/glassy

Identified June 26, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white; Luster: Vitreous/glassy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & geological history

Formed by the precipitation of silica-rich hydrothermal fluids in cavities (vugs) within igneous or sedimentary rocks. This process can happen over millions of years as minerals crystallize along the interior walls of a hollow cavity.

Uses & applications

Extensively used in jewelry making, watches (as oscillator crystals), electronics for frequency control, decorative home decor, and mineral collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Clear quartz is often called 'Rock Crystal' and was believed by many ancient cultures to be permanently frozen ice.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by steel) and lack of cleavage. Look for characteristic hexagonal crystal points inside hollow or broken nodules. Common in Brazil, Madagascar, and the USA.

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