Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
Category
Browse organic mineral specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
Black Limestone with Calcite Veining
Limestone (CaCO3) with Calcite (CaCO3) inclusions
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert with Quartz Veining
Silicon Dioxide (SiO2)
Chert Pebble with Inclusion
Microcrystalline Quartz (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Tiger Shark Fossil Tooth
Galeocerdo cuvier (fossilized)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
River Rock
Silica-rich water-worn rock
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Chert (potentially Jasper)
Microcrystalline Quartz (SiO2)
Chert (Septarian Nodules-like)
Silicon dioxide (SiO2)
Sandstone (Ferruginous)
Clastic Sedimentary Rock (Sandstone)
Chert Concretion (Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Travertine (Tufa)
Chemical Sedimentary Rock (CaCO3)
Black Onyx
Cryptocrystalline Quartz (SiO2 with organic/iron impurities)
Blue Agate (Tumbled and Dyed)
Silicon Dioxide (SiO2) with likely organic dyes
Banded Sedimentary Rock (Siltstone/Mudstone with concretion)
Siltstone with Ferruginous Banding
Fossilized Shark Tooth (Megalodon or Carcharocles fragment)
Elasmobranchii (Fossilized tooth root / crown section)
Petrified Wood
Silicified Wood (Permineralized organic tissue)
Chert (Flint variety)
Microcrystalline context of Quartz (SiO2)
Pink Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O)
Ferruginous Sandstone Concretion (Ironstone Phosphorite)
Ferruginous Sandstone (variable Fe-oxide/hydroxide composition)
Jasper with Agate and Quartz Inclusions
Silicon Dioxide (SiO2) - Chalcedony / Quartz aggregate
Petrified Wood
Silicified Wood (SiO2)
Yellow Chert (Jasper)
Silicon Dioxide (SiO2)
Banded Agate (Dyed)
SiO2 (Silicon Dioxide / Microcrystalline Quartz)
Moss Agate
Chalcedony (SiO2) with inclusions of manganese or iron oxides
Pyrite in Shaly Matrix
Iron Sulfide (FeS2)
Chert Concretion
Microcrystalline Quartz (SiO2)
Chert (with Limestone and Iron Oxide staining)
Cryptocrystalline Quartz (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Chert (concretionary/nodular variant)
Microcrystalline Quartz (SiO2) with possible fossil or mineral inclusions
Mammoth Tooth
Mammuthus primigenius (Tooth fragment)
Petrified Wood
Silicified wood (primarily SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2 / Quartz pseudomorph after wood)
Black Chert
Carbonaceous Chert (Silicon dioxide, SiO2)
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)