Rock Identifier

Category

Organic Structure (Not A Rock)

Browse organic structure (not a rock) specimens identified by the Rock Identifier community.

Learn about Organic Structure (Not A Rock) in the encyclopedia

Bituminous Shale

Bituminous Shale

Black Shale

Oil Shale

Petrified Wood

Crocodile Jasper

Crocodile Jasper

Opalized Wood

Rock Salt

Rock Gypsum

Coral Rock

Asphalt Rock

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

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

Chert (Jasper)

Silicon Dioxide (SiO2)

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

Chert (Yellow/Brown Jasper)

Silicon Dioxide (SiO2)

Vuggy Limestone (Carbonate Sedimentary Rock with Vuggy Porosity (CaCO3)) — sedimentary

Vuggy Limestone

Carbonate Sedimentary Rock with Vuggy Porosity (CaCO3)

Fossiliferous Limestone (Carbonate sedimentary rock (CaCO3) with bioclasts) — sedimentary

Fossiliferous Limestone

Carbonate sedimentary rock (CaCO3) with bioclasts

Tree Agate (also known as Dendritic Agate) (Silicon Dioxide with inclusions (SiO2 + Mn/Fe)) — mineral

Tree Agate (also known as Dendritic Agate)

Silicon Dioxide with inclusions (SiO2 + Mn/Fe)

Conglomerate (Conglomerate) — Sedimentary

Conglomerate

Conglomerate

Sandstone (likely Fossilized Wood or Concrete Simulacrum) (Arenite / Silicified Wood / Anthropogenic Concrete) — sedimentary

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Chert (Polished/Worn) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Polished/Worn)

Microcrystalline quartz (SiO2)

Chert (Flint) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (Flint)

Chert (Cryptocrystalline Silica, SiO2)

Petrified Wood (Silicified Wood (primarily quartz/chalcedony replacing organic wood structure, SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily quartz/chalcedony replacing organic wood structure, SiO2)

Chert with Quartz Veining (Microcrystalline silica (SiO2)) — sedimentary

Chert with Quartz Veining

Microcrystalline silica (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Travertine (Terrestrial Sedimentary Limestone (CaCO3)) — sedimentary

Travertine

Terrestrial Sedimentary Limestone (CaCO3)

Sandstone (with carbonaceous plant fragments) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with carbonaceous plant fragments)

Arenite (composed primarily of SiO2)

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

Chert (White Chert or Flint)

Microcrystalline Quartz (SiO2)

Banded Gneiss (River Rock/Pebble) (Gneiss (specifically a banded variety often found as a river rock)) — Metamorphic Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Slate (Slate (Foliated metamorphic rock)) — metamorphic

Slate

Slate (Foliated metamorphic rock)

Septarian Nodule (Septarian Concretion (CaCO3 with Siderite/Limonite streaks)) — sedimentary

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Limonite streaks)

Glauconite (Greensand) ((K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂) — sedimentary

Glauconite (Greensand)

(K, Na)(Fe3⁰, Al, Mg)₂(Si, Al)₄O₁₀(OH)₂

Chert (Nodule) (Chert (composition: SiO2)) — sedimentary

Chert (Nodule)

Chert (composition: SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicon Dioxide Fossilized Wood (SiO2)) — fossil

Petrified Wood

Silicon Dioxide Fossilized Wood (SiO2)

Petrified Wood (Silicified wood (Quartz/Chalcedony - SiO2)) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

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

Chert (Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (primarily Chalcedony/Quartz, SiO2)) — fossil

Petrified Wood

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Fossilized Bone Fragment (Vertebrate Fossil Material (Apatite/Calcium Phosphate)) — fossil

Fossilized Bone Fragment

Vertebrate Fossil Material (Apatite/Calcium Phosphate)

Red coral cabochon (likely dyed or reconstructed coral) (Corallium rubrum or other calcareous coral; chiefly aragonite (CaCO₃)) — gemstone

Red coral cabochon (likely dyed or reconstructed coral)

Corallium rubrum or other calcareous coral; chiefly aragonite (CaCO₃)

Gray River Pebble (likely Limestone or Siltstone) (Sedimentary Rock (Calcium Carbonate or Siliciclastic)) — sedimentary

Gray River Pebble (likely Limestone or Siltstone)

Sedimentary Rock (Calcium Carbonate or Siliciclastic)

Petrified Wood (Silicified Wood (primarily Quartz/SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily Quartz/SiO2)

Chert (Jasper/Agate Peat) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Agate Peat)

Microcrystalline Quartz (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Yellow Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Yellow Chert

Microcrystalline Quartz (SiO2)

Sandstone Concretion (Sedimentary Clastic Rock (Silicate-rich)) — sedimentary

Sandstone Concretion

Sedimentary Clastic Rock (Silicate-rich)

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

Chert / Chalcedony Nodules

Microcrystalline 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)

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

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Iron-stained) (Chert (SiO2)) — sedimentary

Chert (Iron-stained)

Chert (SiO2)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper) (Microcrystalline Quartz (SiO2) with hematite impurities) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2) with hematite impurities

Coprolite (Fossilized Feces) — fossil

Coprolite

Fossilized Feces