Rock Identifier

Category

Organic Structure (Not A Rock)

Browse organic structure (not a rock) specimens identified by the Rock Identifier community.

Learn about Organic Structure (Not A Rock) in the encyclopedia

Bituminous Shale

Bituminous Shale

Black Shale

Oil Shale

Petrified Wood

Crocodile Jasper

Crocodile Jasper

Opalized Wood

Rock Salt

Coral Rock

Rock Gypsum

Asphalt Rock

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Fossilized Bone Fragment (Vertebrate Fossil) — fossil

Fossilized Bone Fragment

Vertebrate Fossil

Fossiliferous Limestone (Calcium Carbonate (CaCO3) with Organic Inclusions) — fossil

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with Organic Inclusions

Limestone with Fossil Fragment (Sedimentary carbonate rock (CaCO3)) — sedimentary

Limestone with Fossil Fragment

Sedimentary carbonate rock (CaCO3)

Jasper (Iron-stained Chert) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Jasper (Silicon Dioxide (Microcrystalline Quartz, SiO2)) — mineral

Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)

Fossilized Dinosaur Skull (Tyrannosaurus rex) (Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica) — sedimentary

Fossilized Dinosaur Skull (Tyrannosaurus rex)

Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica

Petrified Wood (Silicified wood (Quartz/Chalcedony replacement) SiO2) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement) SiO2

Chert (Yellow Jasper/Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper/Flint)

Microcrystalline Quartz (SiO2)

Coal (Bituminous Coal / Anthracite) — sedimentary

Coal

Bituminous Coal / Anthracite

Sandstone (likely Fossiliferous Sandstone) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (likely Fossiliferous Sandstone)

Clastic sedimentary rock (primarily SiO2)

Microcrystalline Quartz (Chert/Agate) (Silicon Dioxide (SiO2)) — sedimentary

Microcrystalline Quartz (Chert/Agate)

Silicon Dioxide (SiO2)

Chert (Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Conglomerate (Conglomerate) — Sedimentary

Conglomerate

Conglomerate

Heart-shaped Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Heart-shaped Limestone

Calcium Carbonate (CaCO3)

Fossiliferous Sandstone / Mudstone (Sedimentary Rock (Clastic with Fossiliferous Inclusions)) — sedimentary

Fossiliferous Sandstone / Mudstone

Sedimentary Rock (Clastic with Fossiliferous Inclusions)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Lignite (Brown Coal) (Humic Lignite (Carbonaceous sedimentary rock)) — sedimentary

Lignite (Brown Coal)

Humic Lignite (Carbonaceous sedimentary rock)

Chert (Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

River Cobble (Sandstone) (Arenite (primarily SiO2)) — sedimentary

River Cobble (Sandstone)

Arenite (primarily SiO2)

Herkimer Diamond (Quartz (Silica - SiO2)) — mineral

Herkimer Diamond

Quartz (Silica - SiO2)

Sandstone (Sandstone (principally SiO2/Silicon Dioxide)) — sedimentary

Sandstone

Sandstone (principally SiO2/Silicon Dioxide)

Glauconitic Sandstone (Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone

Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)

Chert Nodule / Ironstone Concretion (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Chert Nodule / Ironstone Concretion

Microcrystalline Quartz (SiO2) with Iron Oxides

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Quartz pebble or seed/crumb (SiO2 (if quartz)) — mineral

Quartz pebble or seed/crumb

SiO2 (if quartz)

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)

Limestone with Calcite Veining (Sedimentary Rock (Calcium Carbonate, CaCO3)) — sedimentary

Limestone with Calcite Veining

Sedimentary Rock (Calcium Carbonate, CaCO3)

Fossilized Coral (Rugosa / Scleractinia (Agatized or Calcitized Coral)) — fossil

Fossilized Coral

Rugosa / Scleractinia (Agatized or Calcitized Coral)

Seashell Fossil (Gastropoda fossil) — fossil

Seashell Fossil

Gastropoda fossil

Ironstone Nodules in Chalk/Limestone (Limonite/Goethite concretions (FeO(OH)·nH2O) in Calcium Carbonate matrix (CaCO3)) — sedimentary

Ironstone Nodules in Chalk/Limestone

Limonite/Goethite concretions (FeO(OH)·nH2O) in Calcium Carbonate matrix (CaCO3)

Fossilized Brain Coral (Diploria labyrinthiformis (Fossilized)) — sedimentary

Fossilized Brain Coral

Diploria labyrinthiformis (Fossilized)

Fossilized Brachiopod (Brachiopoda (Phylum)) — fossil

Fossilized Brachiopod

Brachiopoda (Phylum)

Geode with Quartz Crystal Cavity (Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix) — sedimentary

Geode with Quartz Crystal Cavity

Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix

Pearl necklace (Pearl (biogenic calcium carbonate, chiefly aragonite; CaCO₃)) — gemstone

Pearl necklace

Pearl (biogenic calcium carbonate, chiefly aragonite; CaCO₃)

Banded Chert (Chert (Silicon Dioxide, SiO2)) — sedimentary

Banded Chert

Chert (Silicon Dioxide, SiO2)

Fossiliferous Limestone (Coquina) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Chert with Calcite Veins (Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions) — sedimentary

Chert with Calcite Veins

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions

Fossil Shell Fragment (possibly Brachiopod or Bivalve) (Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca) — sedimentary

Fossil Shell Fragment (possibly Brachiopod or Bivalve)

Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca

Chert (Limestone/Flint variant) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Limestone/Flint variant)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Shale (Shale (Fine-grained clastic sedimentary rock)) — sedimentary

Shale

Shale (Fine-grained clastic sedimentary rock)

Hag Stone (Perforated Sedimentary Rock (typically Flint or Limestone)) — sedimentary

Hag Stone

Perforated Sedimentary Rock (typically Flint or Limestone)