Rock Identifier

Category

Mineral (Biogenic Replacement)

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

Chert (with Limestone and Iron Oxide staining) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (with Limestone and Iron Oxide staining)

Cryptocrystalline Quartz (SiO2)

Jasper (Silicon dioxide (SiO2) with impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with impurities

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Hematite with Magnetite (Iron Oxide (Fe2O3)) — mineral

Hematite with Magnetite

Iron Oxide (Fe2O3)

Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Calcite

Calcite (Calcium Carbonate, CaCO3)

Green Fluorite (Fluorite (Calcium Fluoride, CaF2)) — mineral

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Magnetite / Hematite mix (Iron Ore) (Fe3O4 (Magnetite) / Fe2O3 (Hematite)) — mineral

Magnetite / Hematite mix (Iron Ore)

Fe3O4 (Magnetite) / Fe2O3 (Hematite)

Bay Scallop Shell (Argopecten irradians (Biogenic Calcium Carbonate / CaCO3)) — sedimentary

Bay Scallop Shell

Argopecten irradians (Biogenic Calcium Carbonate / CaCO3)

Tiger's Eye (Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2) — metamorphic

Tiger's Eye

Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2

Kidney Stone (Medical Specimen) (Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O) — Mineral (Biogenic)

Kidney Stone (Medical Specimen)

Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O

Mineral (Biogenic)

Rhodonite (Rhodonite (Manganese Iron Magnesium Calcium Silicate) - (Mn+2,Fe+2,Mg,Ca)SiO3) — mineral

Rhodonite

Rhodonite (Manganese Iron Magnesium Calcium Silicate) - (Mn+2,Fe+2,Mg,Ca)SiO3

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

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

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

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Carnelian variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Carnelian variety)

Microcrystalline Quartz (SiO2)

Coprolite (Fossilized feces (various taxa)) — sedimentary

Coprolite

Fossilized feces (various taxa)

Jasper (Silicon Dioxide (SiO2)) — sedimentary

Jasper

Silicon Dioxide (SiO2)

Chert (Flint variety) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (Flint variety)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Fossilized Coral (Petoskey Stone or Rugose Coral) (Antophyllum (Hexagonaria) or Scleractinia (CaCO3)) — sedimentary

Fossilized Coral (Petoskey Stone or Rugose Coral)

Antophyllum (Hexagonaria) or Scleractinia (CaCO3)

Green Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Green Jasper

Jasper (Silicon Dioxide, SiO2)

Calamites (Fossilized Horsetail) (Calamites suckowii (Family: Calamitaceae)) — sedimentary

Calamites (Fossilized Horsetail)

Calamites suckowii (Family: Calamitaceae)

Pyrite (Iron Disulfide (FeS2)) — Mineral

Pyrite

Iron Disulfide (FeS2)

Orthoceras Fossil in Limestone (Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone) — sedimentary

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone

Pyrite (Iron Disulfide (FeS2)) — mineral

Pyrite

Iron Disulfide (FeS2)

Carnelian (Carnelian (SiO2 with Iron Oxide impurities)) — mineral

Carnelian

Carnelian (SiO2 with Iron Oxide impurities)

Sodalite (Sodalite - Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

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

Rhodonite

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

Chalcedony (Common Opal variant) (Silicon dioxide (SiO2) with varying levels of hydration) — mineral

Chalcedony (Common Opal variant)

Silicon dioxide (SiO2) with varying levels of hydration

Jasper Agate (Silicon dioxide (SiO2)) — mineral

Jasper Agate

Silicon dioxide (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Fossilized Brachiopod (Phylum Brachiopoda (replaced by Calcite/CaCO3)) — sedimentary

Fossilized Brachiopod

Phylum Brachiopoda (replaced by Calcite/CaCO3)

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood / Chalcedony (SiO2)) — sedimentary

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood / Chalcedony (SiO2)

Chert (variously known as Flint or Microcrystalline Quartz) (Silicon dioxide (SiO2)) — sedimentary

Chert (variously known as Flint or Microcrystalline Quartz)

Silicon dioxide (SiO2)

Bivalve Fossil (Internal Mold/Steinkern) (Class Bivalvia (Fossilized Mold)) — sedimentary

Bivalve Fossil (Internal Mold/Steinkern)

Class Bivalvia (Fossilized Mold)

Calcite (Calcite (Mineral; CaCO₃)) — Mineral

Calcite

Calcite (Mineral; CaCO₃)

Celestine (or Celestite) (Strontium sulfate (SrSO4)) — mineral

Celestine (or Celestite)

Strontium sulfate (SrSO4)

Celestite (Celestine) (Strontium sulfate (SrSO4)) — mineral

Celestite (Celestine)

Strontium sulfate (SrSO4)

Tiger's Eye (Small Polished Bead) (Pseudomorph of Quartz after Crocidolite (SiO2)) — mineral

Tiger's Eye (Small Polished Bead)

Pseudomorph of Quartz after Crocidolite (SiO2)

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

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Magnetite (Magnetite (Fe3O4)) — mineral

Magnetite

Magnetite (Fe3O4)

Chert (Common Opal/Agate inclusion) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Common Opal/Agate inclusion)

Microcrystalline Quartz (SiO2)