mineral

Quartz Geode

Crystalline Quartz (SiO2) within a sedimentary or volcanic host

Hardness: 7 (Mohs scale); Color: Clear to white crystals within a tan/grey rind; Luster: Vitreous (glassy) crystals with a dull/earthy exterior; Crystal Structure: Trigonal (hexagonal prisms); Cleavage: None/Conchoidal fracture.

Hardness: 7 (Mohs scale)
Color: Clear to white crystals within a tan/grey rind
Luster: Vitreous (glassy) crystals with a dull/earthy exterior

Identified June 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed via the precipitation of mineral-rich water within hollow cavities of sedimentary rocks (like limestone) or volcanic gas bubbles. Over millions of years, crystals grow inward toward the center.

Uses & applications

Popular for educational purposes, home decor, geological collecting, and metaphysical uses. Some industrial quartz is used in electronics and glassmaking.

Geological facts

The term geode comes from the Greek word 'Geoides' meaning earth-like. Unlike vugs, geodes are discrete units that can be separated from their host rock.

Field identification & locations

Identified by a round or sub-round exterior that feels lighter than a solid rock of the same size. Commonly found in desert regions of the SW United States, Morocco, and Brazil.

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Mineral/Rock

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Metamorphic Rock

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mineral