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

Coral Rock

Rock Gypsum

Asphalt Rock

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

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

Petrified Wood

Silicified Wood (primarily SiO2)

Amber (Succinates (Fossilized Tree Resin)) — mineraloid

Amber

Succinates (Fossilized Tree Resin)

Amber (Succinite (C10H16O)) — mineral

Amber

Succinite (C10H16O)

Lepidodendron Fossil (Scale Tree) (Lepidodendron) — fossil

Lepidodendron Fossil (Scale Tree)

Lepidodendron

Glauconitic Sandstone (Greensand) (Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)) — sedimentary

Glauconitic Sandstone (Greensand)

Glauconitic Sandstone ((K, Na)(Fe3+, Al, Mg)2(Si, Al)4O10(OH)2)

Petrified Wood (Silicified Wood) (Silicified Wood / Silicon Dioxide (SiO2)) — metamorphic

Petrified Wood (Silicified Wood)

Silicified Wood / Silicon Dioxide (SiO2)

Gastropod Steinkern (Fossil Snail Internal Mold) (Class Gastropoda (Internal Mold)) — sedimentary

Gastropod Steinkern (Fossil Snail Internal Mold)

Class Gastropoda (Internal Mold)

Seashell Fossil (Invertebrate fossil (phylum Mollusca)) — fossil

Seashell Fossil

Invertebrate fossil (phylum Mollusca)

Chert (Jasper-bearing) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Jasper-bearing)

Chert (Silicon Dioxide, SiO2)

Chert (specifically a fragment with Desert Varnish) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (specifically a fragment with Desert Varnish)

Microcrystalline quartz (SiO2)

Granite (Granite (a felsic intrusive igneous rock)) — Igneous Rock

Granite

Granite (a felsic intrusive igneous rock)

Fossilized Coral (Scleractinian Anthozoa (Fossilized Calcium Carbonate, CaCO3)) — sedimentary

Fossilized Coral

Scleractinian Anthozoa (Fossilized Calcium Carbonate, CaCO3)

Siltstone with plant fossil impression (Sedimentary rock with Archaeopteris or Calamites flora impression) — fossil

Siltstone with plant fossil impression

Sedimentary rock with Archaeopteris or Calamites flora impression

Blue Quartzite (Dyed) (Metamorphosed Quartz-rich Sandstone (SiO2 with organic dye)) — metamorphic

Blue Quartzite (Dyed)

Metamorphosed Quartz-rich Sandstone (SiO2 with organic dye)

Jasper (specifically a banded or dark variety) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper (specifically a banded or dark variety)

Silicon Dioxide (SiO2) with impurities

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — mineral

Pickled Dragon Eggs (Fictional Interpretation: Purple Agate or Amethyst Geodes)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Petrified Wood (Silicified wood (Quartz/Chalcedony replacement of organic matter)) — fossil

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement of organic matter)

Fossiliferous limestone (likely ammonite/gastropod-bearing) (Bioclastic limestone; predominantly calcite (CaCO₃)) — sedimentary

Fossiliferous limestone (likely ammonite/gastropod-bearing)

Bioclastic limestone; predominantly calcite (CaCO₃)

Chert with Calcite Veining (Microcrystalline Quartz (SiO2) with Calcium Carbonate (CaCO3) veins) — sedimentary

Chert with Calcite Veining

Microcrystalline Quartz (SiO2) with Calcium Carbonate (CaCO3) veins

Ferruginous Chert (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Ferruginous Chert

Microcrystalline Quartz (SiO2) with Iron Oxides

Green Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Green Jasper

Silicon Dioxide (SiO2) with impurities

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

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Limestone (specifically Fossiliferous or Crinoidal Limestone) (Calcium Carbonate (CaCO3) - Calcite Rock) — sedimentary

Limestone (specifically Fossiliferous or Crinoidal Limestone)

Calcium Carbonate (CaCO3) - Calcite Rock

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

Chert (Pebble)

Silicon Dioxide (SiO2)

Possible fossilized ammonite or concretion (Indeterminate fossil specimen; possibly an ammonoid mold/cast in iron-rich sedimentary rock) — fossil

Possible fossilized ammonite or concretion

Indeterminate fossil specimen; possibly an ammonoid mold/cast in iron-rich sedimentary rock

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Green Jasper (with Quartz veining) (Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2) — sedimentary

Green Jasper (with Quartz veining)

Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2

Septarian Nodule (Polished) (Septarian concretion (Calcite, Aragonite, Limestone)) — sedimentary

Septarian Nodule (Polished)

Septarian concretion (Calcite, Aragonite, Limestone)

Chert (Chert Nodule with Cortex) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Chert Nodule with Cortex)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Shungite (Carbonaceous rock (primarily amorphous carbon)) — Mineraloid

Shungite

Carbonaceous rock (primarily amorphous carbon)

Chert (Brown variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brown variety)

Silicon Dioxide (SiO2)

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

Fossilized Wood / Petrified Wood

Petrified Wood (Silicified Flora)

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

Petrified Wood

Silicified wood (primarily SiO2)

River Rock (Silica-rich water-worn rock) — sedimentary

River Rock

Silica-rich water-worn rock

Chert (River Cobble) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (River Cobble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Pumice (Pumice (volcanic rock)) — Igneous

Pumice

Pumice (volcanic rock)

Petrified Wood (Fossilized Wood (SiO2 replacing organic matter)) — fossil

Petrified Wood

Fossilized Wood (SiO2 replacing organic matter)

Chert (with Manganese Oxide coating) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Manganese Oxide coating)

Microcrystalline 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

Chert (Jasper/Flint variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2)

Fossilized Brachiopod (Brachiopoda (e.g., Atrypa or Rhynchonellida)) — fossil

Fossilized Brachiopod

Brachiopoda (e.g., Atrypa or Rhynchonellida)