Rock Identifier

Category

Sedimentary (Alluvial Deposit)

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

Microcrystalline Limestone Pebble (Carbonate sedimentary rock (Calcium Carbonate, CaCO3)) — sedimentary

Microcrystalline Limestone Pebble

Carbonate sedimentary rock (Calcium Carbonate, CaCO3)

Echinoid Fossil (Sea Urchin) (Echinoidea (specifically likely Schizaster or similar genus), calcium carbonate (CaCO3)) — sedimentary

Echinoid Fossil (Sea Urchin)

Echinoidea (specifically likely Schizaster or similar genus), calcium carbonate (CaCO3)

Limestone Pebble (Calcium Carbonate (CaCO3)) — sedimentary

Limestone Pebble

Calcium Carbonate (CaCO3)

Jasper with Quartz Veining (Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony) — sedimentary

Jasper with Quartz Veining

Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony

River Stone / Siltstone (Siltstone (composed of lithified silt)) — sedimentary

River Stone / Siltstone

Siltstone (composed of lithified silt)

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

Red Chert (Jasper)

Silicon Dioxide (SiO2)

Jasper (Petrified Wood variant) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) with iron oxide inclusions

Carnelian (Carnelian (a variety of Chalcedony, SiO2)) — mineral

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Selenite (Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O) — mineral

Selenite

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Calcite (Optical Grade/Iceland Spar) (Calcium Carbonate (CaCO3)) — mineral

Calcite (Optical Grade/Iceland Spar)

Calcium Carbonate (CaCO3)

Yellow Chalcedony (likely carnelian or yellow agate) (Silicon Dioxide (SiO₂)) — mineral

Yellow Chalcedony (likely carnelian or yellow agate)

Silicon Dioxide (SiO₂)

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pyrite (on Quartz matrix) (Iron Sulfide (FeS2)) — mineral

Pyrite (on Quartz matrix)

Iron Sulfide (FeS2)

River Pebble (likely Quartzite or Chert) (Silicon Dioxide (SiO2)) — metamorphic or sedimentary

River Pebble (likely Quartzite or Chert)

Silicon Dioxide (SiO2)

metamorphic or sedimentary

River Pebble (Likely Quartzite or Chert) (Silicon Dioxide (SiO2)) — metamorphic or sedimentary

River Pebble (Likely Quartzite or Chert)

Silicon Dioxide (SiO2)

metamorphic or sedimentary

Optical Calcite (Iceland Spar) (Calcium Carbonate (CaCO3)) — mineral

Optical Calcite (Iceland Spar)

Calcium Carbonate (CaCO3)

Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Chert (specifically Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint)

Cryptocrystalline Quartz (SiO2)

Red Jasper (Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)) — sedimentary

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions, SiO2)

Quartzite Pebble (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Sandstone (Wonderstone) (Silicified Sandstone / Orthoquartzite with Liesegang rings) — sedimentary

Sandstone (Wonderstone)

Silicified Sandstone / Orthoquartzite with Liesegang rings

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (and/or Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and/or Flint)

Silicon Dioxide (SiO2)

Coquina (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcium Carbonate - CaCO3)

Chalk (Calcium Carbonate (CaCO3)) — sedimentary

Chalk

Calcium Carbonate (CaCO3)

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

Sandstone

Clastic sedimentary rock (primarily SiO2)

Chert Breccia (Yellow Jasper) (Silicon Dioxide (SiO2) - Brecciated Chert) — sedimentary

Chert Breccia (Yellow Jasper)

Silicon Dioxide (SiO2) - Brecciated Chert

Coquina (Coquina (Bioclastic Limestone)) — sedimentary

Coquina

Coquina (Bioclastic Limestone)

Petoskey Stone (Hexagonaria percarinata (Fossilized Rugose Coral)) — sedimentary

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Siltstone (Siltstone (primarily SiO2 with Al2O3 and Fe2O3)) — sedimentary

Siltstone

Siltstone (primarily SiO2 with Al2O3 and Fe2O3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

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

Coquina

Biogenic Limestone (mostly Calcium Carbonate, CaCO3)

Chert / River Pebble (Microcrystalline Silica (SiO2)) — sedimentary

Chert / River Pebble

Microcrystalline Silica (SiO2)

Tiger Iron (Tiger Iron (composite of Tiger's Eye, Red Jasper, and Hematite)) — metamorphic

Tiger Iron

Tiger Iron (composite of Tiger's Eye, Red Jasper, and Hematite)

Sandstone Pebble (Arenite (primarily Quartz, SiO2)) — sedimentary

Sandstone Pebble

Arenite (primarily Quartz, SiO2)

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

Sandstone

Arenite (composed primarily of SiO2)

Grey Chalcedony (Tumbled) (Chalcedony (SiO2)) — mineral

Grey Chalcedony (Tumbled)

Chalcedony (SiO2)

Chalcedony (specifically Agate or Carnelian pebble) (Chalcedony (Microcrystalline Quartz, SiO2)) — mineral

Chalcedony (specifically Agate or Carnelian pebble)

Chalcedony (Microcrystalline Quartz, SiO2)

Optical Calcite (Iceland Spar) (Calcite (Calcium Carbonate, CaCO3)) — mineral

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Jasper (Wonderstone/Banded Jasper) (Silicon Dioxide (SiO2) with iron oxide impurities) — sedimentary (chemical/biological origin) or volcanic-related metamorphic

Jasper (Wonderstone/Banded Jasper)

Silicon Dioxide (SiO2) with iron oxide impurities

sedimentary (chemical/biological origin) or volcanic-related metamorphic

Travertine (Terrestrial Sedimentary Limestone (CaCO3)) — sedimentary

Travertine

Terrestrial Sedimentary Limestone (CaCO3)