Rock Identifier

Category

Mineral (Biogenic Replacement)

Browse mineral (biogenic replacement) specimens identified by the Rock Identifier community.

Small marine shell fragment (Calcareous shell, primarily calcium carbonate (aragonite or calcite); exact taxon indeterminate) — fossil

Small marine shell fragment

Calcareous shell, primarily calcium carbonate (aragonite or calcite); exact taxon indeterminate

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Galena (Lead(II) sulfide (PbS)) — mineral

Galena

Lead(II) sulfide (PbS)

Jasper (Silicon dioxide (SiO2)) — Mineral / Sedimentary

Jasper

Silicon dioxide (SiO2)

Mineral / Sedimentary

Magnetite (Iron(II,III) oxide (Fe3O4)) — mineral

Magnetite

Iron(II,III) oxide (Fe3O4)

Calamites (Fossil) (Calamites sp. (Tracheophyta, Equisetopsida)) — sedimentary

Calamites (Fossil)

Calamites sp. (Tracheophyta, Equisetopsida)

Fossilized Shark Tooth (Sand Tiger) (Carcharias taurus (fossil specimen)) — sedimentary

Fossilized Shark Tooth (Sand Tiger)

Carcharias taurus (fossil specimen)

Fossilized Coprolite (Coprolite (fossilized feces)) — sedimentary

Fossilized Coprolite

Coprolite (fossilized feces)

Chert Nodule (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodule

Microcrystalline Quartz (SiO2)

Shark Tooth Fossil (Chondrichthyes (class) fossilized tooth) — fossil

Shark Tooth Fossil

Chondrichthyes (class) fossilized tooth

Fossil bivalve shell (Fossilized or mineral-replaced bivalve mollusk shell; exact genus/species requires locality and detailed morphology) — fossil

Fossil bivalve shell

Fossilized or mineral-replaced bivalve mollusk shell; exact genus/species requires locality and detailed morphology

Polished brecciated jasper (likely ocean jasper or red jasper) (Microcrystalline quartz/chalcedony (SiO₂) with iron-oxide hematite/goethite and dark volcanic or manganese-rich inclusions) — mineral

Polished brecciated jasper (likely ocean jasper or red jasper)

Microcrystalline quartz/chalcedony (SiO₂) with iron-oxide hematite/goethite and dark volcanic or manganese-rich inclusions

Fossil bone or tooth fragment (Indeterminate fossilized vertebrate bone/tooth; taxonomic identification is not possible from this blurred image) — fossil

Fossil bone or tooth fragment

Indeterminate fossilized vertebrate bone/tooth; taxonomic identification is not possible from this blurred image

Fossilized Shark Tooth (Elasmobranchii (Class) fossil) — fossil

Fossilized Shark Tooth

Elasmobranchii (Class) fossil

Fossilized Shark Tooth (Chondrichthyes tooth) — fossil

Fossilized Shark Tooth

Chondrichthyes tooth

Fossilized bone or tooth fragment (Indeterminate fossil bone; possibly mammalian or reptilian) — fossil

Fossilized bone or tooth fragment

Indeterminate fossil bone; possibly mammalian or reptilian

Brachiopod Fossil (Phylum Brachiopoda) — fossil

Brachiopod Fossil

Phylum Brachiopoda

Rhodonite (Manganese silicate: (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese silicate: (Mn,Fe,Mg,Ca)SiO3

Flint (Chert Flake / Drill Tool) (SiO2 (Microcrystalline Quartz)) — sedimentary

Flint (Chert Flake / Drill Tool)

SiO2 (Microcrystalline Quartz)

Chert Nodules (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodules

Microcrystalline Quartz (SiO2)

Pyrite (Fool's Gold) in Matrix (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold) in Matrix

Iron Disulfide (FeS2)

Metallic sulfide-bearing rock, likely galena-rich ore (Galena (lead sulfide, PbS), possibly mixed with pyrite/chalcopyrite and host rock) — mineral

Metallic sulfide-bearing rock, likely galena-rich ore

Galena (lead sulfide, PbS), possibly mixed with pyrite/chalcopyrite and host rock

Fossilized Syringopora (Piping Organ Coral) (Syringopora (Extinct Genus of Tabulate Coral)) — sedimentary

Fossilized Syringopora (Piping Organ Coral)

Syringopora (Extinct Genus of Tabulate Coral)

Chert / Chalcedony Blend (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Chalcedony Blend

Microcrystalline Quartz (SiO2)

Coprolite (Coprolite) — sedimentary

Coprolite

Coprolite

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Fossil Shell (Brachiopod or Mollusk fossil) — fossil

Fossil Shell

Brachiopod or Mollusk fossil

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

Chert (Black Flint)

Cryptocrystalline Quartz (SiO2)

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

Chert

Chert (Microcrystalline Quartz, SiO2)

Fossilized Shark Tooth (Chondrichthyes (Class)) — fossil

Fossilized Shark Tooth

Chondrichthyes (Class)

Dinosaur Claw Fossil (Fossilized Theropod Claw (Vertebrate Palaeontological Specimen)) — fossil

Dinosaur Claw Fossil

Fossilized Theropod Claw (Vertebrate Palaeontological Specimen)

Megalodon Shark Tooth (Otodus megalodon) — fossil

Megalodon Shark Tooth

Otodus megalodon

Fossil Coral (Petoskey / Favosites) (Favosites sp. / Hexagonaria sp. (Calcite/Silica pseudomorph)) — fossil

Fossil Coral (Petoskey / Favosites)

Favosites sp. / Hexagonaria sp. (Calcite/Silica pseudomorph)

Fossil coral (Colonial scleractinian coral fossil, likely a tabulate or honeycomb coral; exact genus requires microscopy) — fossil

Fossil coral

Colonial scleractinian coral fossil, likely a tabulate or honeycomb coral; exact genus requires microscopy

Fossilized coral or carbonate fossil fragment (Calcareous fossil, likely colonial coral (order Hexacorallia; uncertain from image)) — fossil

Fossilized coral or carbonate fossil fragment

Calcareous fossil, likely colonial coral (order Hexacorallia; uncertain from image)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Banded Flint (Chert) (Silicon Dioxide (SiO2)) — sedimentary

Banded Flint (Chert)

Silicon Dioxide (SiO2)

Queen Conch Shell (Biogenic Calcium Carbonate) (Aliger gigas (synonym Strombus gigas); Composition: Aragonite (CaCO3)) — mineral

Queen Conch Shell (Biogenic Calcium Carbonate)

Aliger gigas (synonym Strombus gigas); Composition: Aragonite (CaCO3)

Polished jasper slab (Jasper, an opaque microcrystalline variety of chalcedony (SiO₂), colored mainly by iron oxides) — mineral

Polished jasper slab

Jasper, an opaque microcrystalline variety of chalcedony (SiO₂), colored mainly by iron oxides

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Galena (Lead(II) sulfide (PbS)) — mineral

Galena

Lead(II) sulfide (PbS)