Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Category
Browse organic (geological interest) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Greenschist
Greenschist facies rock
Limestone (Crushed Gravel)
Limestone (Calcium Carbonate, CaCO3)
Chert (Flint) with Limestone Matrix
Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)
Fossil Shell (Bivalve)
Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal)
Petrified Wood
Silicified Wood (primarily SiO2)
Geode (Unopened)
Silica-rich concretion (SiO2)
Chert Nodule (with Geode cavity)
Cryptocrystalline Quartz (SiO2)
Amber
Succinite / Fossilized Resin (C10H16O)
Petrified Wood
Silicon Dioxide Fossilized Wood (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Biomicrite / Limestone with fossils
Fossilized Shark Tooth
Chondrichthyes (Class) fossil
Olive Sea Shell Fossil
Oliva sp. (Calcium Carbonate, CaCO3)
Ironstone Concretion
Goethite-rich Siltstone / Siderite (FeCO3)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Fossil-bearing ironstone or weathered concretion
Indeterminate; likely ferruginous sandstone/concretion containing a partial fossil impression
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variant)
Silicon Dioxide (SiO2)
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Graphite Schist
C (Carbonaceous Schist)
Chert (Black Chert/Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony/SiO2)
Chert (and Fossilized Brachiopod shell)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Jasper variation)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
River Stone (Chert/Siltstone)
Cryptocrystalline Quartz (SiO2) with trace impurities
Petrified Wood
Silicified wood (Quartz variant, SiO2)
Chalcedony / Agate with Botryoidal Quartz
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcedony replacement)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Cryptocrystalline Quartz (Silicon Dioxide, SiO2)