Rock Identifier

Category

Organic (Geological Interest)

Browse organic (geological interest) specimens identified by the Rock Identifier community.

Chert (often referred to as Flint or Jasper when pigmented) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often referred to as Flint or Jasper when pigmented)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Jasper variant) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz / Quartzite (Silicon Dioxide (SiO2)) — metamorphic

Quartz / Quartzite

Silicon Dioxide (SiO2)

Chert (with Fossiliferous Silicification) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (with Fossiliferous Silicification)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Granite (Phaneritic plutonic rock (composed of Quartz, Feldspar, and Mica/Amphibole)) — igneous

Granite

Phaneritic plutonic rock (composed of Quartz, Feldspar, and Mica/Amphibole)

Chert (Gravel) (Chert (Cryptocrystalline silicon dioxide, SiO2)) — sedimentary

Chert (Gravel)

Chert (Cryptocrystalline silicon dioxide, SiO2)

Quartz (Vein Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Chert (Flint variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Granite (Phaneritic plutonic rock (primarily Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Phaneritic plutonic rock (primarily Quartz, Alkali Feldspar, and Plagioclase)

Blue Calcite (Calcium Carbonate (CaCO3)) — Mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Chert (with Iron Staining) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (with Iron Staining)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Granite (Pink/Potassium-rich) (Pink Granite (contains K-Feldspar, Quartz, and Plagioclase)) — igneous

Granite (Pink/Potassium-rich)

Pink Granite (contains K-Feldspar, Quartz, and Plagioclase)

Sand Dollar Fossil (Echinoidea) (Class Echinoidea (likely order Clypeasteroida), CaCO3 (Calcite)) — sedimentary

Sand Dollar Fossil (Echinoidea)

Class Echinoidea (likely order Clypeasteroida), CaCO3 (Calcite)

Calcite (likely a tumbled specimen) (Calcite (CaCO
3
)) — Mineral

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

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

Chert / Flint

Cryptocrystalline Quartz (SiO2)

Granodiorite (Granodiorite (phaneritic intrusive igneous rock)) — igneous

Granodiorite

Granodiorite (phaneritic intrusive igneous rock)

Chert (Jasper) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Cryptocrystalline Quartz (SiO2)

Granite (Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)) — igneous

Granite

Granite (Felsic Plutonic Rock / SiO2 + Al2O3 + K2O + Na2O + CaO + FeO + MgO)

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

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Aragonite (Aragonite (CaCO3)) — mineral

Aragonite

Aragonite (CaCO3)

Greisen (Greisen) — Metamorphic

Greisen

Greisen

Dark-colored Igneous Rock (likely Basalt or Diabase) (Basalt (extrusive igneous) or Diabase (intrusive igneous)) — Igneous Rock

Dark-colored Igneous Rock (likely Basalt or Diabase)

Basalt (extrusive igneous) or Diabase (intrusive igneous)

Chert (variant of Flint) (Chert (SiO2)) — Sedimentary

Chert (variant of Flint)

Chert (SiO2)

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

Chert (specifically Blue Chert/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Chert (Yellow Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper)

Silicon Dioxide (SiO2)

Diorite (Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)) — igneous

Diorite

Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)

Mica Schist (Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)) — metamorphic

Mica Schist

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)

Marble (Recrystallized Carbonate Rock (CaCO3)) — metamorphic

Marble

Recrystallized Carbonate Rock (CaCO3)

Mookaite (Mookaite Jasper) (Silicified Radiolarite (SiO2 with iron oxides)) — sedimentary

Mookaite (Mookaite Jasper)

Silicified Radiolarite (SiO2 with iron oxides)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Chert (Black Chert/Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Black Chert/Flint)

Silicon Dioxide (SiO2)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Chert (Grey-Green Flint) (Microcrystalline silicon dioxide (SiO2)) — sedimentary

Chert (Grey-Green Flint)

Microcrystalline silicon dioxide (SiO2)

Pink Granite (Phaneritic Felsic Igneous Rock) — igneous

Pink Granite

Phaneritic Felsic Igneous Rock

Diorite (Salt and Pepper Rock) (Diorite) — igneous

Diorite (Salt and Pepper Rock)

Diorite

Petrified Wood (Silicified wood (primarily Silicon Dioxide, SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

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

Calcite

Calcite (Calcium Carbonate, CaCO3)

Quartz with Mica/Chlorite inclusions (Silicon Dioxide (SiO2) with phyllosilicate inclusions) — igneous/metamorphic mineral specimen

Quartz with Mica/Chlorite inclusions

Silicon Dioxide (SiO2) with phyllosilicate inclusions

igneous/metamorphic mineral specimen