Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Category
Browse sedimentary (cryptocrystalline silica) specimens identified by the Rock Identifier community.
Blue Chalcedony
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Coral (Agatized Coral)
Anthozoa (Agatized Fossil)
Chert (Jasper/Agate)
Cryptocrystalline Quartz (SiO2)
Chalcedony (River Pebble)
Silicon Dioxide (SiO2)
Chert/Flint nodule or weathered river rock
Microcrystalline or cryptocrystalline silica (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (specifically Silex or Flint)
Microcrystalline Quartz (SiO2)
Chert (Common Opal/Jasper variety)
Microcrystalline Quartz (SiO2) with hydration
Silicified Snail Fossil
Gastropod (likely replaced by Chalcedony/Quartz - SiO2)
Jasper Pebble
Microcrystalline Quartz (SiO2)
Chert Nodule
Microcrystalline Quartz (SiO2)
Blue Chalcedony (Tumbled)
Silicon Dioxide (SiO2)
Chalcedony (Carnelian / Agate pebble)
Microcrystalline Quartz (SiO2)
Jasper Pebble
Microcrystalline Quartz (SiO2)
Jasper
Microcrystalline Quartz (SiO2)
Chert or Chalcedony
Microcrystalline Quartz (SiO2)
Chert (Black Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Tumbled brown stone, possibly jasper or weathered chert
Uncertain; likely microcrystalline quartz (SiO₂), potentially iron-stained jasper/chert
Chert (Flint Nodule)
Silicon Dioxide (SiO2)
Jasper (Brown Jasper)
Microcrystalline Quartz (Chalcedony), SiO2
Chalcedony (Carnelian / Agate)
Silicon Dioxide (SiO2)
Common Opal / Chert
Hydrated silica (SiO2·nH2O) or Microcrystalline Quartz (SiO2)
Chalcedony (Agate Nodules)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chalcedony (Grey/White Agate)
Silicon Dioxide (SiO₂)
Chalcedony (Blue/Grey Lace Agate)
Silicon Dioxide (SiO2)
Chert (Chert Nodule with Chalky Cortex)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Jasper/Agate variety)
Silicon Dioxide (SiO2)
Chalcedony (Agate / Jasper Pebble)
Silicon Dioxide (SiO2)
Chert (Fossiliferous)
Chert (Cryptocrystalline Silica/SiO2)
Banded Agate (specifically Carnelian Agate)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Jasper / Chert (River Stone)
Cryptocrystalline Quartz (SiO2)
Chalcedony (Agate/Carnelian pebbles)
Cryptocrystalline Quartz (SiO2)
Banded Agate
Cryptocrystalline Quartz (SiO2)
Blue Chalcedony
Cryptocrystalline Quartz (SiO2)
Chert / Flint Arrowheads and Artifacts
Cryptocrystalline quartz (SiO2)
Chert (Nodule)
Cryptocrystalline Quartz (SiO2)
Chert (Arrowhead)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Quartz Pebble (Chalcedony / River Pebble)
Silicon Dioxide (SiO2)