Chert Nodule / Ironstone Concretion
Microcrystalline Quartz (SiO2) with Iron Oxides
Category
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Chert Nodule / Ironstone Concretion
Microcrystalline Quartz (SiO2) with Iron Oxides
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
Petrified Wood
Silicified wood / Permineralized wood (SiO2)
Coal (Anthracite / Bituminous)
Organic Sedimentary Rock (Carbon-based)
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Black Shale
Argillaceous Chert/Shale
Petrified Wood
Silicified Wood (SiO2)
Tree Agate
Silicon Dioxide (SiO2) with Dendritic Inclusions
Sea Shell (Mollusk Shell)
Calcium Carbonate (Aragonite/Calcite)
Jasper
Silicon dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Petrified Wood
Silicified Wood (SiO2)
Shale (or Slate / Coal / Jet)
Laminated fine-grained sedimentary rock (predominantly clay minerals)
Weathered River Rock (likely Chert or Basalt with algae)
Silicon dioxide (SiO2) with organic biofilm
Gray River Pebble (likely Limestone or Siltstone)
Sedimentary Rock (Calcium Carbonate or Siliciclastic)
Coprolite
Fossilized Feces
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Siltstone with Fossil Cast
Sedimentary Rock (Siltstone / Fine-grained Sandstone)
Chert
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified wood (primarily Quartz, SiO2)
Chert / Chalcedony
Silicon Dioxide (SiO2)
Fossilized Shark Tooth
Chondrichthyes (Class)
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 principal component)
Chert (Flint Nodules)
Chert (Silicon Dioxide, SiO2)
Geode with Quartz Crystal Cavity
Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix
Petrified Wood
Silicified Wood (SiO2)
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Fossil-bearing Sedimentary Rock
Sedimentum cum fossili
Fossiliferous Shale
Laminated Mudrock with plant fossils
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Septarian Nodule
Septarian Nodule (Calcite, Aragonite, and Limestone/Claystone)
Granite / Feldspar gravel
Granite (felsic intrusive igneous rock)
Agatized Petrified Wood
Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Limestone Concretion (Botryoidal/Calcareous Nodules)
Calcium Carbonate Concretion (CaCO3)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Polished/Tumbled)
Silicon Dioxide (SiO2)
Sandstone (Glauconitic)
Glauconitic Quartz Sandstone (SiO2 + (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Dinosaur Fossil Tooth
Vertebrate Fossilized Tooth
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2 with chlorite inclusions)