mineral

Quartz Geode

Crystalline Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to colorless; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to colorless
Luster: Vitreous to greasy

Identified June 3, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White to colorless; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Formed in cavities (vugs) within volcanic or sedimentary rocks through the precipitation of mineral-rich groundwater over thousands to millions of years.

Uses & applications

Used in home decor, lapidary arts, jewelry, and by collectors for its aesthetic crystal formations. High-purity quartz is also vital for electronics.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. These geodes often started as a gas bubble in lava or a hollow space in sediment.

Field identification & locations

Identified by its hexagonal crystal points, hardness that scratches glass, and the presence of a hollow or filled cavity (druzy). Found worldwide, with major deposits in Brazil, Uruguay, and the US (Iowa/Utah/Arizona).