Rock Identifier

Category

Organic (Geological Interest)

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

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

Chert (Jasper/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Chert (White-Grey variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White-Grey variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Yellow Jasper / Chert (Jasper (Silica/Quartz) - SiO2) — sedimentary

Yellow Jasper / Chert

Jasper (Silica/Quartz) - SiO2

Fossil Shell (Bivalve) (Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)) — sedimentary

Fossil Shell (Bivalve)

Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)

Chert (White Chert/Flint) (Chert (SiO2)) — sedimentary

Chert (White Chert/Flint)

Chert (SiO2)

Chert (specifically Flint or Common Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Common Chert)

Silicon Dioxide (SiO2)

Chert (variations include Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variations include Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Fossil) (Silicified Wood (SiO2)) — sedimentary

Petrified Wood (Silicified Fossil)

Silicified Wood (SiO2)

Gastropod Fossil (Snail Steinkern) (Class Gastropoda (internal mold)) — sedimentary

Gastropod Fossil (Snail Steinkern)

Class Gastropoda (internal mold)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

White seed-bead gemstone strand, likely freshwater pearl or shell pearl (Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image) — gemstone

White seed-bead gemstone strand, likely freshwater pearl or shell pearl

Pearl: nacreous calcium carbonate, chiefly aragonite (CaCO₃) in conchiolin; identification uncertain from image

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Moqui Marble (Shaman Stone) (Ironstone Concretion (Goethite/Hematite Shell)) — sedimentary

Moqui Marble (Shaman Stone)

Ironstone Concretion (Goethite/Hematite Shell)

Quartz (Chert/Chalcedony variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Jasper (Silicon dioxide, SiO2) — Mineral

Jasper

Silicon dioxide, SiO2

Petrified Wood / Jasper Chert (Silicified Wood / Microcrystalline Quartz (SiO2)) — sedimentary

Petrified Wood / Jasper Chert

Silicified Wood / Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily Silicon Dioxide, SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — fossil

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified wood (primarily SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily SiO2)

Fossil Coral (Rugosa or Solitary Coral) (Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)) — sedimentary

Fossil Coral (Rugosa or Solitary Coral)

Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)

Chert Nodules in Limestone (Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)) — sedimentary

Chert Nodules in Limestone

Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

Lemon (Mock specimen mimicking Citrine/Sulfur) (Citrus x limon) — Organic (Biological specimen)

Lemon (Mock specimen mimicking Citrine/Sulfur)

Citrus x limon

Organic (Biological specimen)

Amber (Succinite (C10H16O)) — mineraloid

Amber

Succinite (C10H16O)

Chalcedony or Chert/Jasper with secondary mineral staining (SiO2 (for chalcedony/quartz) with possible secondary copper minerals (e.g., CuSiO3·nH2O for chrysocolla, Cu2(CO3)(OH)2 for malachite) or iron oxides/hydroxides.) — Mineral, potentially a rock with chalcedony/jasper.

Chalcedony or Chert/Jasper with secondary mineral staining

SiO2 (for chalcedony/quartz) with possible secondary copper minerals (e.g., CuSiO3·nH2O for chrysocolla, Cu2(CO3)(OH)2 for malachite) or iron oxides/hydroxides.

Mineral, potentially a rock with chalcedony/jasper.

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Agatized Petrified Wood (Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood) — metamorphic

Agatized Petrified Wood

Silicon Dioxide (SiO2) - Chalcedony pseudomorph after Wood

Pitted Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Pitted Limestone

Calcium Carbonate (CaCO3)

Anthracite Coal (Carbon (with trace impurities)) — sedimentary

Anthracite Coal

Carbon (with trace impurities)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Prehnite with Epidote inclusions (Prehnite: Ca2Al(AlSi3O10)(OH)2; Epidote: Ca2(Al,Fe)3(SiO4)3(OH)) — Mineral

Prehnite with Epidote inclusions

Prehnite: Ca2Al(AlSi3O10)(OH)2; Epidote: Ca2(Al,Fe)3(SiO4)3(OH)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Pyrite Concretion (Iron Sulfide (FeS2) in Sedimentary Matrix) — sedimentary

Pyrite Concretion

Iron Sulfide (FeS2) in Sedimentary Matrix

Fossilized Vertebra (Chordata fossil (Vertebra)) — fossil

Fossilized Vertebra

Chordata fossil (Vertebra)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossiliferous Limestone (with Crinoids) (CaCO3 (Calcium Carbonate)) — sedimentary

Fossiliferous Limestone (with Crinoids)

CaCO3 (Calcium Carbonate)

Chert (likely brown flint) (Microcrystalline quartz, SiO₂ (chalcedonic quartz aggregate)) — sedimentary

Chert (likely brown flint)

Microcrystalline quartz, SiO₂ (chalcedonic quartz aggregate)

Fossiliferous Chert (with Fossil Shells) (Silicon Dioxide (SiO2) with biogenic inclusions) — sedimentary

Fossiliferous Chert (with Fossil Shells)

Silicon Dioxide (SiO2) with biogenic inclusions

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)