Rock Identifier

Category

Mineral (Biogenic Replacement)

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

Nacre (Mother of Pearl) (Nacre (Biogenic Aragonite/Calcite composite, CaCO3)) — mineral

Nacre (Mother of Pearl)

Nacre (Biogenic Aragonite/Calcite composite, CaCO3)

Pyrite (on host rock) (Iron Sulfide (FeS2)) — mineral

Pyrite (on host rock)

Iron Sulfide (FeS2)

Coquina (Biogenic Limestone (Calcite/Aragonite base, CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcite/Aragonite base, CaCO3)

Galena (Lead Sulfide (PbS)) — mineral

Galena

Lead Sulfide (PbS)

Fossil Shark Tooth (Lamniformes (order) - likely Cretalamna or Carcharias species) — fossil

Fossil Shark Tooth

Lamniformes (order) - likely Cretalamna or Carcharias species

Fossilized Dinosaur Skull (Tyrannosaurus rex) (Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica) — sedimentary

Fossilized Dinosaur Skull (Tyrannosaurus rex)

Tyrannosaurus rex (permineralized fossil), rich in Hydroxylapatite/Silica

Dinosaur Fossil (Tyrannosaurus rex skull replica/specimen) (Tyrannosaurus rex (fossilized in permineralized sedimentary matrix)) — sedimentary

Dinosaur Fossil (Tyrannosaurus rex skull replica/specimen)

Tyrannosaurus rex (fossilized in permineralized sedimentary matrix)

Rhodochrosite (Manganese Carbonate (MnCO3)) — mineral

Rhodochrosite

Manganese Carbonate (MnCO3)

Tooth or shell fragment (likely fossilized marine material) (Indeterminate; possibly a fossil fish tooth or mollusk shell fragment composed mainly of calcium carbonate (CaCO₃)) — fossil

Tooth or shell fragment (likely fossilized marine material)

Indeterminate; possibly a fossil fish tooth or mollusk shell fragment composed mainly of calcium carbonate (CaCO₃)

Fossil Coral / Crinoid Stem section (Anthozoa / Crinoidea fossil) — fossil

Fossil Coral / Crinoid Stem section

Anthozoa / Crinoidea fossil

Specular Hematite (Hematite (Iron(III) oxide, Fe2O3)) — mineral

Specular Hematite

Hematite (Iron(III) oxide, Fe2O3)

Galena (Lead sulfide (PbS)) — mineral

Galena

Lead sulfide (PbS)

Fossilized Shell Fragment (Bivalvia or Gastropoda (Class) fragment) — fossil

Fossilized Shell Fragment

Bivalvia or Gastropoda (Class) fragment

Galena (Lead Sulfide (PbS)) — mineral

Galena

Lead Sulfide (PbS)

Poppy Jasper (Microcrystalline Quartz (SiO2) with mineral inclusions) — sedimentary

Poppy Jasper

Microcrystalline Quartz (SiO2) with mineral inclusions

Rodonite (Rhodonite (MnSiO3)) — mineral

Rodonite

Rhodonite (MnSiO3)

Mineral and Rock Collection (Assorted) (Mixed collection including Quartz (SiO2), Jasper (SiO2 with impurities), Rose Quartz, and Aventurine) — mineral

Mineral and Rock Collection (Assorted)

Mixed collection including Quartz (SiO2), Jasper (SiO2 with impurities), Rose Quartz, and Aventurine

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

Galena

Lead(II) sulfide (PbS)

Pyrite and Calcite (or Barite) Specimen (Iron Sulfide (FeS2) with Calcium Carbonate (CaCO3)) — mineral

Pyrite and Calcite (or Barite) Specimen

Iron Sulfide (FeS2) with Calcium Carbonate (CaCO3)

Cowrie Shell Fossil (Cypraea sp.) — fossil

Cowrie Shell Fossil

Cypraea sp.

Pyrite (Iron sulfide (FeS2)) — mineral

Pyrite

Iron sulfide (FeS2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Bivalve Fossil (Clam) (Class Bivalvia (e.g., Exogyra or Gryphaea species)) — fossil

Bivalve Fossil (Clam)

Class Bivalvia (e.g., Exogyra or Gryphaea species)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Botryoidal Chalcedony (Silicon Dioxide (SiO2)) — mineral

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Polished brown flint/chert (likely) (Microcrystalline quartz, SiO₂ (chalcedonic flint/chert)) — sedimentary

Polished brown flint/chert (likely)

Microcrystalline quartz, SiO₂ (chalcedonic flint/chert)

Water and Silt (Sedimentary Environment) (Suspended Sediment / H2O (dihydrogen monoxide)) — sedimentary

Water and Silt (Sedimentary Environment)

Suspended Sediment / H2O (dihydrogen monoxide)

Triceratops Fossil (Triceratops horridus) — fossil

Triceratops Fossil

Triceratops horridus

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Murex Fossil (Muricidae (Calcium Carbonate fossilization)) — fossil

Murex Fossil

Muricidae (Calcium Carbonate fossilization)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Fossil Snail (Gastropoda (fossilized)) — fossil

Fossil Snail

Gastropoda (fossilized)

Fossil Sea Urchin (Echinoid) (Echinoidea fossil (often replaced by silica or calcite)) — fossil

Fossil Sea Urchin (Echinoid)

Echinoidea fossil (often replaced by silica or calcite)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Fossil Shell (Phylum Mollusca (Gastropod fossil)) — fossil

Fossil Shell

Phylum Mollusca (Gastropod fossil)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Fossilized Sea Urchin (Echinoid) (Echinoidea (Class) - likely replaced by Calcite or Quartz) — sedimentary

Fossilized Sea Urchin (Echinoid)

Echinoidea (Class) - likely replaced by Calcite or Quartz

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Fossilized Dinosaur Bone (Perineralized Bone (Fluorapatite/Quartz replacement)) — fossil

Fossilized Dinosaur Bone

Perineralized Bone (Fluorapatite/Quartz replacement)

Fossilized Bivalve Shell (Bivalvia (fossil specimen)) — sedimentary

Fossilized Bivalve Shell

Bivalvia (fossil specimen)

Fossilized Fish (Lepidotes) (Lepidotes sp. (Order: Lepisosteiformes)) — sedimentary

Fossilized Fish (Lepidotes)

Lepidotes sp. (Order: Lepisosteiformes)