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 / Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Jasper

Microcrystalline Quartz (SiO2)

Chert (Jasper/Ironstone variety) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Chert (Jasper/Ironstone variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Limestone (Calcium carbonate (CaCO3)) — sedimentary

Limestone

Calcium carbonate (CaCO3)

Travertine (Tufa) (Chemical Limestone (CaCO3)) — sedimentary

Travertine (Tufa)

Chemical Limestone (CaCO3)

Chert (Chocolate or Brown Flint) (Chert (SiO2)) — sedimentary

Chert (Chocolate or Brown Flint)

Chert (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

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

Chert (Jasper/Mudstone)

Silicon Dioxide (SiO2)

Polished gray metamorphic stone, likely marble (Calcite-dominant marble (CaCO₃), possibly dolomitic marble) — metamorphic

Polished gray metamorphic stone, likely marble

Calcite-dominant marble (CaCO₃), possibly dolomitic marble

Tumbled amber (Fossilized tree resin; predominantly polymerized diterpenoid resin (succinite when Baltic-type)) — fossil

Tumbled amber

Fossilized tree resin; predominantly polymerized diterpenoid resin (succinite when Baltic-type)

Chert Nodule (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodule

Microcrystalline Quartz (SiO2)

Jasper (Silicon Dioxide (Microcrystalline Quartz, $SiO_2$)) — sedimentary

Jasper

Silicon Dioxide (Microcrystalline Quartz, $SiO_2$)

Dragon Stone (Ohko Stone (Argillaceous sedimentary rock)) — sedimentary

Dragon Stone

Ohko Stone (Argillaceous sedimentary rock)

Bituminous Coal (Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)) — sedimentary

Bituminous Coal

Organic Sedimentary Rock (composed mostly of carbon with sulfur and hydrogen)

Polished moss agate / dendritic agate (Microcrystalline quartz (SiO₂) with iron- and manganese-oxide inclusions) — mineral

Polished moss agate / dendritic agate

Microcrystalline quartz (SiO₂) with iron- and manganese-oxide inclusions

Pyrite in Shale (Iron Sulfide (FeS2) in Argillaceous Shale) — sedimentary

Pyrite in Shale

Iron Sulfide (FeS2) in Argillaceous Shale

Fossilized Wood / Petrified Wood (Petrified Wood (Silicified Flora)) — fossil

Fossilized Wood / Petrified Wood

Petrified Wood (Silicified Flora)

Chert (Arrowhead variety) (Chert (SiO2)) — sedimentary

Chert (Arrowhead variety)

Chert (SiO2)

Chert (River Pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Coquina Limestone (Fossiliferous Limestone) (Calcareous bioclastic sedimentary rock (CaCO3)) — sedimentary

Coquina Limestone (Fossiliferous Limestone)

Calcareous bioclastic sedimentary rock (CaCO3)

Chert (Yellow/Brown variety) (Chert (SiO2)) — sedimentary

Chert (Yellow/Brown variety)

Chert (SiO2)

Chert (Flint) (Silicon dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon dioxide (SiO2)

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

Chert (specifically Flint or Jasper variant)

Cryptocrystalline Quartz (SiO2)

Chert (Field Stone) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (or Fossiliferous Limestone) (Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)) — sedimentary

Chert (or Fossiliferous Limestone)

Microcrystalline Quartz (SiO2) / Calcium Carbonate (CaCO3)

Ruby in Fuchsite (Corundum (Al2O3) in Fuchsite (K(Al,Cr)3Si3O10(OH)2)) — Mineral

Ruby in Fuchsite

Corundum (Al2O3) in Fuchsite (K(Al,Cr)3Si3O10(OH)2)

Petrified Wood (Silicified Wood (Permineralized organic matter, głównie $SiO_2$)) — fossil

Petrified Wood

Silicified Wood (Permineralized organic matter, głównie $SiO_2$)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Petrified Wood (Silicified wood (Quartz/Chalcedony/Opal)) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony/Opal)

Chert (Nodule/Pebble) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Nodule/Pebble)

Chert (Silicon Dioxide, SiO2)

Chert (Gray Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Picture Jasper (Silicon Dioxide (SiO2) with iron oxide and organic impurities) — sedimentary

Picture Jasper

Silicon Dioxide (SiO2) with iron oxide and organic impurities

Chert (Flint) (Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)

Fossilized Shell Fragment / Mother of Pearl (Calcium Carbonate (CaCO3) - Aragonite/Calcite biomineral) — fossil

Fossilized Shell Fragment / Mother of Pearl

Calcium Carbonate (CaCO3) - Aragonite/Calcite biomineral

Coquina / Shelly Sandstone (Calcareous Sandstone / Coquina) — sedimentary

Coquina / Shelly Sandstone

Calcareous Sandstone / Coquina

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

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (varietal: Jasper or Flint) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (varietal: Jasper or Flint)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Fossiliferous Limestone (Crinoid stem fragment) (Crinoidea (Phylum Echinodermata) in Calcite matrix) — fossil

Fossiliferous Limestone (Crinoid stem fragment)

Crinoidea (Phylum Echinodermata) in Calcite matrix

Pink Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — mineraloid

Pink Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Shale (Fissile mudstone (primarily clay minerals and silt-sized quartz)) — sedimentary

Shale

Fissile mudstone (primarily clay minerals and silt-sized quartz)

Fossiliferous Limestone (Calcite-rich Fossiliferous Limestone (CaCO3)) — sedimentary

Fossiliferous Limestone

Calcite-rich Fossiliferous Limestone (CaCO3)

Fossiliferous Limestone (Limestone (CaCO3 with Limonite/Goethite staining)) — sedimentary

Fossiliferous Limestone

Limestone (CaCO3 with Limonite/Goethite staining)