Rock Identifier

Category

Sedimentary (Fossilized)

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

White Marble (Recrystallized Calcite (CaCO3)) — metamorphic

White Marble

Recrystallized Calcite (CaCO3)

Dendritic Siltstone (or Mudstone) (Siltstone with Manganese Oxide dendrites) — sedimentary

Dendritic Siltstone (or Mudstone)

Siltstone with Manganese Oxide dendrites

Lignite (Brown Coal) (Lignite (C189H155O6N3S)) — sedimentary

Lignite (Brown Coal)

Lignite (C189H155O6N3S)

Ferruginous Sandstone (Sandstone with Iron Oxide (Limonite/Goethite)) — sedimentary

Ferruginous Sandstone

Sandstone with Iron Oxide (Limonite/Goethite)

Chert (Nodule) (Crystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Crystalline Silicon Dioxide (SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

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

Sandstone

Arenite (composed primarily of SiO2)

Chert (Yellow Jasper/Quartzite Pebble) (Microcrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper/Quartzite Pebble)

Microcrystalline Silicon Dioxide (SiO2)

Conglomerate (Conglomerate rock) — sedimentary

Conglomerate

Conglomerate rock

Chert (Gravel Bit) (Microcrystalline silica (SiO2)) — sedimentary

Chert (Gravel Bit)

Microcrystalline silica (SiO2)

Ferruginous Sandstone (Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)) — sedimentary

Ferruginous Sandstone

Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)

White Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

White Quartz Pebble

Silicon Dioxide (SiO2)

Chert (with Iron Staining) (Silicon Dioxide (SiO2)) — sedimentary

Chert (with Iron Staining)

Silicon Dioxide (SiO2)

Limonite Concretion (Ironstone) (Limonite / Goethite (FeO(OH)·nH2O)) — sedimentary

Limonite Concretion (Ironstone)

Limonite / Goethite (FeO(OH)·nH2O)

Limonite Pseudomorph after Pyrite (Limonite (FeO(OH)·nH2O) replacing Pyrite (FeS2)) — mineral

Limonite Pseudomorph after Pyrite

Limonite (FeO(OH)·nH2O) replacing Pyrite (FeS2)

Ammonite Fossil (Ammonoidea (Calcium carbonate - CaCO3)) — sedimentary

Ammonite Fossil

Ammonoidea (Calcium carbonate - CaCO3)

Chert (varieties include Flint and Jasper) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Ferruginous Sandstone (Sandstone (arenite) with Limonite/Goethite cement) — sedimentary

Ferruginous Sandstone

Sandstone (arenite) with Limonite/Goethite cement

Chert (Green variety) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Green variety)

Chert (Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Common Opal in Host Rock (Hydrated Silica (SiO2·nH2O)) — mineraloid

Common Opal in Host Rock

Hydrated Silica (SiO2·nH2O)

Chert (Iron-stained) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert / Jasper

Silicon Dioxide (SiO2)

Chert (Light Grey / Flint variant) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Light Grey / Flint variant)

Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)

Limonite-pseudomorph after Pyrite (Prophecy Stone) (Goethite and Limonite secondary minerals (FeO(OH)·nH2O) replacing Pyrite (FeS2)) — mineral

Limonite-pseudomorph after Pyrite (Prophecy Stone)

Goethite and Limonite secondary minerals (FeO(OH)·nH2O) replacing Pyrite (FeS2)

Red Quartz (Carnelian/Red Jasper Agate) (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — mineral

Red Quartz (Carnelian/Red Jasper Agate)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

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

Sandstone

Arenite (composed primarily of SiO2)

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

Chert (Pink variety/Jasper)

Silicon Dioxide (SiO2)

River Stone (Basalt or Siltstone with banding) (Polished Basaltic or Siliciclastic River Cobble) — igneous or sedimentary

River Stone (Basalt or Siltstone with banding)

Polished Basaltic or Siliciclastic River Cobble

igneous or sedimentary

Chert (often called Flint or Jasper when pigmented) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper when pigmented)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Petrified Wood

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

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

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

Chert (Black Chert / Flint)

Silicon Dioxide (SiO2)

Calcite (Calcium Carbonate (CaCO3)) — mineral

Calcite

Calcium Carbonate (CaCO3)

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

Chert / Flint

Chert (Microcrystalline Quartz, SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Siltstone (Siltstone (primarily composed of SiO2 with various clay minerals)) — sedimentary

Siltstone

Siltstone (primarily composed of SiO2 with various clay minerals)

Jasper (Silicon dioxide (SiO2) with iron impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with iron impurities

Chert (varietal: Jasper or Flint) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (varietal: Jasper or Flint)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (Cherty Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Cherty Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper (Silicon dioxide (SiO2) with iron oxide impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with iron oxide impurities