Ironstone Concretion
Siderite or Hematite Concretion
sedimentary
Category
Organic Specimen (Fossil)
Browse organic specimen (fossil) specimens identified by the Rock Identifier community.
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Amber (Burmite)
Fossilized tree resin (Succinite variant)
Organic mineraloid
Shiva's Eye (Cat's Eye Shell)
Operculum of Turbo marmoratus
fossil
Fossilized Shark Tooth
Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron
sedimentary
Amber
Succinurite (C10H16O)
mineraloid
Chert / Fossilized Burrow Cast
Microcrystalline Quartz (SiO2) with Trace Carbonates
sedimentary
Fossilized Shark Tooth (Eroded)
Carcharodon sp. or Otodus sp. fragment (likely)
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Devil's Toenail (Fossil Oyster)
Gryphaea arcuata (Calcium Carbonate, CaCO3)
sedimentary
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Fossilized Shark Tooth (Basal Bone)
Otodus sp. (Mineralized Hydroxyapatite)
sedimentary
Ammonite fossil
Fossilized ammonoid cephalopod; likely an involute ammonite, exact genus/species indeterminate
fossil
Amber
Succinite / Fossilized Tree Resin
fossil
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, SiO2)
fossil
Fossilized Shark Tooth (Otodus)
Otodus obliquus
fossil
Petrified Wood
Silicified Wood (Permineralized Lycopsid, Conifer, or Hardwood)
fossil
Bivalve Fossil (Clam Stone)
Phylum Mollusca, Class Bivalvia
fossil
Fossilized Shark Tooth (Anterior/Lateral)
Otodus megalodon or Carcharodon carcharias (fossilized)
fossil
Petrified Wood
Silicified Wood (SiO2 permineralization)
fossil
Amber
Fossilized Tree Resin (Succinite for Baltic varieties)
fossil
Chert Concretion (Flint)
Silicon Dioxide (SiO2)
sedimentary
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3)
sedimentary
Tumbled fossiliferous limestone
Bioclastic limestone, likely crinoidal or shell-rich limestone (calcite, CaCO₃)
sedimentary
Fossilized Shark Tooth (Megalodon or Carcharocles fragment)
Elasmobranchii (Fossilized tooth root / crown section)
fossil
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Fossilized Gastropod in Limestone
Gastropoda (Class) in Fossiliferous Limestone
sedimentary
Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Belemnoit (Fossil)
Belemnoidea (Order), Rostrum / Guard
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossilized Coral
Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous sandstone with plant fossils
Likely fossil-bearing siliciclastic sedimentary rock; apparent fragments may be fossil wood or leaf impressions, but species cannot be determined from the image
fossil
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
metamorphic
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Petrified wood
Silicified fossil wood, primarily quartz (SiO₂) replacing cellulose
fossil
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate, CaCO3)
sedimentary
Amber (with potentially inclusions)
Succinite (Fossilized Tree Resin)
Mineraloid
Possible chert or weathered quartzite fragment
Microcrystalline quartz (SiO₂), identification uncertain from the photograph
sedimentary
Shale fragment
Shale (Laminated Mudstone)
sedimentary
Fossiliferous limestone
Calcarenite/bioclastic limestone, predominantly calcite (CaCO₃)
sedimentary
Fossil Coral
Hexagonaria or Rugose coral fossil (replaced by silica/chalcedony)
fossil