mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: White to translucent exterior with dark crystalline interior; Luster: Vitreous to dull; Crystal structure: Trigonal (hexagonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: White to translucent exterior with dark crystalline interior
Luster: Vitreous to dull

Identified April 26, 2026More mineral →

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Physical properties

Formation & geological history

Formed as secondary mineralization in cavities (vugs) within volcanic or sedimentary rocks. Silica-rich hydrothermal fluids precipitate crystals over thousands of years.

Uses & applications

Commonly used for educational purposes, small collectibles, ornamental stone, and as metaphysical 'healing' stones.

Geological facts

Geodes are essentially 'frozen' bubbles in rock. While the outside looks like an ordinary stone, the interior can contain spectacular crystal formations like druzy quartz, amethyst, or chalcedony.

Field identification & locations

Identify by looking for a hollow or crystal-lined cavity within a round or nodular rinded rock. Commonly found in desert regions, stream beds, or areas with ancient volcanic activity.