sedimentary
Geode
Quartz nodule
AI-generated identification · may be incorrectHardness 7 on Mohs scale, rough chalky exterior, vitreous quartz interior crystals, specific gravity 2.65.
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Physical properties
Hardness 7 on Mohs scale, rough chalky exterior, vitreous quartz interior crystals, specific gravity 2.65.
Formation & geological history
Formed when mineral-rich groundwater fills cavities in sedimentary or volcanic rock, precipitating silica over millions of years.
Uses & applications
Popular in lapidary arts, jewelry, crystal healing, and as collector display specimens.
Geological facts
Geodes often contain stunning quartz or calcite crystal hollows hidden beneath an unassuming, bumpy outer rind.
Field identification & locations
Identify by their spherical, knobby exterior and hollow center lined with crystals when cracked open; common in limestone formations.
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