sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
Hardness of 7 on the Mohs scale, clear to white color, vitreous luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.
Identified More sedimentary →
Explore Quartz Geode in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 7 on the Mohs scale, clear to white color, vitreous luster, hexagonal crystal system, conchoidal fracture with no true cleavage, specific gravity of 2.65.
Formation & geological history
Formed in cavities in sedimentary or volcanic rocks where silica-rich groundwater percolates through, slowly depositing microscopic quartz crystals over millions of years.
Uses & applications
Used in lapidary arts, specimen collecting, jewelry making, and ornamental decoration.
Geological facts
Geodes appear as ordinary, unassuming rocks on the outside, but cracking them open reveals a stunning, hollow cavity lined with sparkling mineral crystals.
Field identification & locations
Look for rounded, nodular rocks with a bumpy or cauliflower-like exterior texture in limestone or volcanic regions. Collectors often tap them with a hammer to reveal the crystal center.
More like this
Other sedimentary specimens
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Fossiliferous Concretion
Septarian Concretion containing Brachiopods/Crinoids
fossil
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
sedimentary
Banded Siltstone / Mudstone Pebble
Siltstone / Argillite
sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary