Rock Identifier

Category

Sedimentary (Fossil)

Browse sedimentary (fossil) specimens identified by the Rock Identifier community.

Limonite (Ironstone) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Ironstone)

Limonite (FeO(OH)·nH2O)

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

Chert / Flint

Microcrystalline Quartz (SiO2)

Chert (specifically Flint or Common Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Milky Quartz with Iron Inclusions (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz with Iron Inclusions

Quartz (Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Sandstone (Red Sandstone / River Stone) (Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)) — sedimentary

Sandstone (Red Sandstone / River Stone)

Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)

Conglomerate (Conglomerate (SiO2 primary clasts with lithic matrix)) — sedimentary

Conglomerate

Conglomerate (SiO2 primary clasts with lithic matrix)

Basalt River Stone (Basalt) — igneous

Basalt River Stone

Basalt

Milky Quartz in Matrix (Silicon Dioxide (SiO2)) — mineral

Milky Quartz in Matrix

Silicon Dioxide (SiO2)

Chert (and Jasper/Flint variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (and Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint in dark varieties) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint in dark varieties)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Sandstone (Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)) — sedimentary

Banded Sandstone

Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)

Chert (Iron-stained) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (Iron-stained)

Chert (Cryptocrystalline Silica, SiO2)

Yellow Quartzite (Onyx Pebble) (Silicon Dioxide (SiO2) - Quartzite) — metamorphic

Yellow Quartzite (Onyx Pebble)

Silicon Dioxide (SiO2) - Quartzite

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Pebble or Cobble (likely composed of sandstone or conglomerate) (Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)) — Sedimentary Rock (possibly a conglomerate or coarse-grained sandstone)

Pebble or Cobble (likely composed of sandstone or conglomerate)

Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)

Sedimentary Rock (possibly a conglomerate or coarse-grained sandstone)

Pyrite (on host rock) (Iron Sulfide (FeS2)) — mineral

Pyrite (on host rock)

Iron Sulfide (FeS2)

Hag Stone (Piddock bored rock) (Calcareous sedimentary rock featuring Pholadidae borings) — sedimentary

Hag Stone (Piddock bored rock)

Calcareous sedimentary rock featuring Pholadidae borings

Ferruginous Sandstone (Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH))) — sedimentary

Ferruginous Sandstone

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH))

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (with Lichen) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with Lichen)

Arenite (composed primarily of SiO2)

Sandstone (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of SiO2)

Banded Chert (River Pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Quartz / Limestone Gravel (SiO2 (Silicon Dioxide) and CaCO3 (Calcium Carbonate)) — igneous and sedimentary mixture

Quartz / Limestone Gravel

SiO2 (Silicon Dioxide) and CaCO3 (Calcium Carbonate)

igneous and sedimentary mixture

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

River Rock (River Cobbles) (Fluvial Conglomerate Clasts (primarily composed of various minerals such as Quartz, SiO2)) — sedimentary

River Rock (River Cobbles)

Fluvial Conglomerate Clasts (primarily composed of various minerals such as Quartz, SiO2)

Sandstone (Quartzose) (Arenite (SiO2 based)) — sedimentary

Sandstone (Quartzose)

Arenite (SiO2 based)

Dalmatian Stone (Peralkaline rhyolite) — igneous

Dalmatian Stone

Peralkaline rhyolite

Sandstone (with Iron Staining) (Clastic Sedimentary Rock (primarily SiO2 with FeO(OH) impurities)) — sedimentary

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily SiO2 with FeO(OH) impurities)

Limestone (specifically Iron-stained or Argillaceous Limestone) (Calcium Carbonate (CaCO3) with Iron Oxide (Fe2O3) impurities) — sedimentary

Limestone (specifically Iron-stained or Argillaceous Limestone)

Calcium Carbonate (CaCO3) with Iron Oxide (Fe2O3) impurities

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous) (Arenite (SiO2 with Fe2O3 inclusions)) — sedimentary

Sandstone (Ferruginous)

Arenite (SiO2 with Fe2O3 inclusions)

Sandstone (Quartz Arenite) (Sandstone (dominated by SiO2 quartz grains)) — sedimentary

Sandstone (Quartz Arenite)

Sandstone (dominated by SiO2 quartz grains)

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Calcareous Sandstone) (Calcareous Sandstone (primarily SiO2 with CaCO3 cement)) — sedimentary

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Sandstone (likely Ferruginous) (Sandstone (SiO2 with iron oxides)) — sedimentary

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

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

Sandstone (Ferruginous)

Arenite with Iron Oxide cement (SiO2 + Fe2O3)

Limonite (FeO(OH)·nH2O (Hydrated iron oxide)) — mineral

Limonite

FeO(OH)·nH2O (Hydrated iron oxide)

Sandstone (River Pebble) (Arenite) — sedimentary

Sandstone (River Pebble)

Arenite