sedimentary
Chalcedony Geode Nodule
Silicon Dioxide (SiO2)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, grayish-brown color, waxy to vitreous luster, and microcrystalline quartz structure with no visible cleavage.
Identified More sedimentary →
Explore Chalcedony Geode Nodule 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, grayish-brown color, waxy to vitreous luster, and microcrystalline quartz structure with no visible cleavage.
Formation & geological history
Formed through the deposition of silica-rich groundwater solutions within cavities of host rocks over millions of years.
Uses & applications
Used primarily in lapidary arts, ornamental carvings, and as collectible mineral specimens.
Geological facts
These hollow nodules often feature intricate quartz or chalcedony linings developed inward from the cavity walls.
Field identification & locations
Identify in the field by its knobby, botryoidal exterior texture and hollow interior lined with tiny crystals; commonly found in limestone or volcanic regions.
More like this
Other sedimentary specimens
Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image
fossil
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary