mineral

Quartz Geode (Cracked Open Fragment)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Clear to white/milky crystals; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Clear to white/milky crystals
Luster: Vitreous (glassy)

Identified February 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Clear to white/milky crystals; Luster: Vitreous (glassy); Crystal structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed as secondary mineral precipitates from hydrothermal fluids or groundwater within cavities of volcanic or sedimentary rocks. Ages vary from recent to millions of years depending on the host rock formation.

Uses & applications

Used in jewelry (lapidary), as decorative display specimens, and for metaphysical collecting. Industrial quartz is used in glassmaking and electronics (though not usually from this form).

Geological facts

Geodes are essentially 'frozen' chemical reactions where mineral-rich water seeped into a hollow bubble and slowly grew crystals inward over thousands of years.

Field identification & locations

Identify in the field by looking for rounded, cauliflower-like exterior nodules that are lighter than solid rocks. Common throughout the American Midwest (Keokuk), Brazil, and Morocco. Test hardness against steel (quartz will scratch steel).

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