Rock Identifier

Category

Sedimentary (Fossilized Organic Matter)

Browse sedimentary (fossilized organic matter) specimens identified by the Rock Identifier community.

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Geode with Quartz and Chalcedony (Silicon Dioxide (SiO2)) — sedimentary

Geode with Quartz and Chalcedony

Silicon Dioxide (SiO2)

Sandstone (Ferruginous) (Arenite with Iron Oxide cement (SiO2 + Fe2O3)) — sedimentary

Sandstone (Ferruginous)

Arenite with Iron Oxide cement (SiO2 + Fe2O3)

Limonitic Sandstone with Inclusion (Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)) — sedimentary

Limonitic Sandstone with Inclusion

Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)

Sandstone (Yellow/Tan) (Clastic sedimentary rock (primarily SiO2 with iron oxide staining)) — sedimentary

Sandstone (Yellow/Tan)

Clastic sedimentary rock (primarily SiO2 with iron oxide staining)

Limestone (Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)) — sedimentary

Limestone

Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Limestone with Calcite Crystals (Calcium Carbonate (CaCO3)) — sedimentary

Limestone with Calcite Crystals

Calcium Carbonate (CaCO3)

Red Sandstone (Clastic Terrigenous Sedimentary Rock (primarily SiO2 with Fe2O3 coating)) — sedimentary

Red Sandstone

Clastic Terrigenous Sedimentary Rock (primarily SiO2 with Fe2O3 coating)

Ferruginous Sandstone (Ironstone) (Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)) — sedimentary

Ferruginous Sandstone (Ironstone)

Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)

Red Sandstone (Iron-rich Sandstone) (Clastic Sedimentary Rock - Quartz Arenite / Arkose with Hematite Cement) — sedimentary

Red Sandstone (Iron-rich Sandstone)

Clastic Sedimentary Rock - Quartz Arenite / Arkose with Hematite Cement

Ferruginous Sandstone (Clastic sedimentary rock (primarily Quartz with Iron Oxide cement)) — sedimentary

Ferruginous Sandstone

Clastic sedimentary rock (primarily Quartz with Iron Oxide cement)

Sandstone (specifically Cross-bedded Sandstone) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (specifically Cross-bedded Sandstone)

Arenite (composed primarily of SiO2)

Chert (Smooth River Pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Gypsum (Wallboard/Drywall) (Calcium Sulfate Dihydrate (CaSO4·2H2O)) — sedimentary

Gypsum (Wallboard/Drywall)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

Ferruginous Sandstone (Iron-rich Sandstone) (Ferruginous Arenite) — sedimentary

Ferruginous Sandstone (Iron-rich Sandstone)

Ferruginous Arenite

Yellow Jasper (Silicon Dioxide (SiO2)) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2)

Gastropod Fossil (Snail Internal Mold) (Gastropoda; internal mold (steinkern), often composed of Calcium Carbonate (CaCO3) or Silica (SiO2)) — sedimentary

Gastropod Fossil (Snail Internal Mold)

Gastropoda; internal mold (steinkern), often composed of Calcium Carbonate (CaCO3) or Silica (SiO2)

Chert (Grey-Green Flint) (Microcrystalline silicon dioxide (SiO2)) — sedimentary

Chert (Grey-Green Flint)

Microcrystalline silicon dioxide (SiO2)

Limonite (Ironstone Concretion) (Limonite (Hydrated iron(III) oxide-hydroxide, mixtures of FeO(OH)·nH2O)) — sedimentary

Limonite (Ironstone Concretion)

Limonite (Hydrated iron(III) oxide-hydroxide, mixtures of FeO(OH)·nH2O)

Chert (White Chert / Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Ammonite Fossil (Polished Half) (Ammonoidea (subclass)) — sedimentary

Ammonite Fossil (Polished Half)

Ammonoidea (subclass)

Jasper (Mookaite style) (Jasper (Silica-rich Microcrystalline Quartz, SiO2)) — sedimentary

Jasper (Mookaite style)

Jasper (Silica-rich Microcrystalline Quartz, SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Schist (specifically Chlorite/Greenschist) (Chlorite Schist) — metamorphic

Schist (specifically Chlorite/Greenschist)

Chlorite Schist

Kyanite (Kyanite (Al2SiO5)) — mineral

Kyanite

Kyanite (Al2SiO5)

Gneiss (with Quartz and Mica) (Gneiss) — metamorphic

Gneiss (with Quartz and Mica)

Gneiss

Chert (Flint) (Chert (microcrystalline quartz)) — sedimentary

Chert (Flint)

Chert (microcrystalline quartz)

Chert (or Flint) (Silicon dioxide (SiO2)) — sedimentary

Chert (or Flint)

Silicon dioxide (SiO2)

Red Sandstone (Arenite with Hematite cementation) — sedimentary

Red Sandstone

Arenite with Hematite cementation

Belemnite Fossil (Guard) (Belemnoidea (Carbonate/Calcite replacement)) — sedimentary

Belemnite Fossil (Guard)

Belemnoidea (Carbonate/Calcite replacement)

Limonite Concretion (Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)) — sedimentary

Limonite Concretion

Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Green Chert (Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Green Chert (Jasper)

Silicon Dioxide (SiO2)

Ferruginous Sandstone (Sandstone, Iron-rich) — sedimentary

Ferruginous Sandstone

Sandstone, Iron-rich

Dalmatian Jasper (Peralkaline rhyolite) — igneous

Dalmatian Jasper

Peralkaline rhyolite

Quartz (likely a form of massive or vein quartz) (Quartz (SiO₂)) — Mineral

Quartz (likely a form of massive or vein quartz)

Quartz (SiO₂)

Sandstone with Quartz Veins (Arenite (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone with Quartz Veins

Arenite (primarily SiO2 with Fe2O3 staining)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone with Secondary Mineral Encrustation (Arenite with Silica/Calcite deposits (SiO2 or CaCO3)) — sedimentary

Sandstone with Secondary Mineral Encrustation

Arenite with Silica/Calcite deposits (SiO2 or CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Fancy Jasper (Ocean Jasper or River Jasper variant) (Silicon Dioxide with inclusions (SiO2)) — sedimentary

Fancy Jasper (Ocean Jasper or River Jasper variant)

Silicon Dioxide with inclusions (SiO2)