Glauconitic Sandstone (Greensand)
Glauconitic Sandstone (Iron-potassium phyllosilicate mineral: (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Category
Sedimentary (Biogenic Sediment Or Biological Remain)
Browse sedimentary (biogenic sediment or biological remain) specimens identified by the Rock Identifier community.
Learn about Sedimentary (Biogenic Sediment Or Biological Remain) in the encyclopedia
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Fossil Shell
Phylum Mollusca (Gastropod fossil)
fossil
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Mosasaur Jaw Fossil in Matrix
Mosasaurus (family Mosasauridae) in Phosphate Sandstone
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Gastropod Internal Mold (Steinkern)
Class Gastropoda fossil mold (Phylum Mollusca)
sedimentary
Brachiopod Fossil in Chert
Phylum Brachiopoda within Microcrystalline Quartz (SiO2)
sedimentary
Fossiliferous Limestone with Brachiopod
Limestone (Calcium Carbonate, CaCO3) with Phylum Brachiopoda fossil
sedimentary
Chert Nodules in Sedimentary Rock
Microcrystalline Quartz (SiO2) within Clastic Matrix
sedimentary
Limonite (Ironstone Concretion)
Limonite (FeO(OH)·nH2O)
mineral/sedimentary
Fossil Shark Tooth
Otodus sp. or Carcharocles sp. (likely fossilized Chondrichthyes)
fossil
Banded Siltstone
Banded Siltstone / Laminated Siltstone
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Bivalve Shell
Bivalvia (fossil specimen)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Claystone Concretion
Septarian Concretion (Ironstone-rich)
sedimentary
Pyrite Concretion (Grapestone)
Iron Sulfide (FeS2) Concretion
sedimentary
Sandstone (Ferruginous)
Sandstone (SiO2 with iron oxide impurities)
sedimentary
Ironstone Concretion
Ironstone (primarily Siderite or Limonite)
sedimentary
Gastropod Fossil (Steinkern)
Class Gastropoda (internal mold)
fossil
Shale
Fissile mudrock (composed of clay-sized particles and detrital grains)
sedimentary
Pyrite in Matrix (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Rounded river cobble, likely weathered sandstone or siltstone
Quartz-rich clastic sedimentary rock; exact identification requires a fresh surface and testing
sedimentary
Amber
Succinicum (Succinite); C10H16O
Mineraloid (Organic)
Sandstone
Arenite (SiO2 predominantly)
sedimentary
Weathered limestone slab
Micritic limestone, primarily calcite (CaCO₃)
sedimentary
Fossil Shark Tooth
Selachii fossil
fossil
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Limestone with Chert Nodule
Carbonate rock (CaCO3) with Microcrystalline Silicon Dioxide (SiO2) inclusion
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Banded Sandstone
Quartz-rich Arenite Sandstone
sedimentary
Amber with dark mineral/organic inclusions
Fossilized plant resin (amber; chiefly polymerized diterpenoid resin)
gemstone
Banded Siltstone
Siltstone with planar bedding
sedimentary
Jasper
Microcrystalline Quartz (Chalcedony), SiO2
sedimentary
Ironstone concretion
Siderite or Limonite concretion (FeCO3 or FeO(OH)·nH2O)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Jasper
Jasper (SiO2 with iron inclusions)
sedimentary
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
sedimentary
Ironstone Concretion
Siderite or Hematite Concretion (FeCO3 or Fe2O3)
sedimentary
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary