Rock Identifier

Category

Organic (Mineraloid)

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

Shale (sub-type: Carbonaceous Shale) (Lutaceous Sedimentary Rock) — sedimentary

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Tufa (Calcareous Tufa) (Calcareous Tufa (CaCO3)) — sedimentary

Tufa (Calcareous Tufa)

Calcareous Tufa (CaCO3)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified wood (Quartz/Chalcedony/SiO2)

Septarian Nodule or Mud Crack Fossil (Septarian Nodule (Concretion)) — sedimentary

Septarian Nodule or Mud Crack Fossil

Septarian Nodule (Concretion)

Chert (variations include Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

Jasper (Agate/Jasper (Microcrystalline Quartz, SiO2)) — sedimentary

Jasper

Agate/Jasper (Microcrystalline Quartz, SiO2)

Jasper (Mookaite variety likely) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Mookaite variety likely)

Silicon Dioxide (SiO2) with iron oxide inclusions

Septarian Nodule (Dragon Stone) (Septarian Concretion (CaCO3 with Siderite and Calcite)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Concretion (CaCO3 with Siderite and Calcite)

Banded Chert (Ironstone/Jasper) (Cryptocrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Banded Chert (Ironstone/Jasper)

Cryptocrystalline Quartz (SiO2) with Iron Oxides

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

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Chert (Jasper variation) (Chert (SiO2)) — sedimentary

Chert (Jasper variation)

Chert (SiO2)

Septarian Nodule (Dragon Stone) (Septarian Geode (CaCO3 + Mg + Fe)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Geode (CaCO3 + Mg + Fe)

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

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (Brecciated or Veined) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brecciated or Veined)

Silicon Dioxide (SiO2)

Chert (Iron-Stained) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-Stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Fossilized Wood (with Coal and Limonite) (Petrified Wood (Silicified or Carbonized Flora)) — sedimentary

Fossilized Wood (with Coal and Limonite)

Petrified Wood (Silicified or Carbonized Flora)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Green variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Green variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood / Chalcedony (SiO2)) — sedimentary

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood / Chalcedony (SiO2)

Jasper (Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)) — sedimentary

Jasper

Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)

Chert (Iron-stained) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Flint) (Chert (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Jasper (Red-Brown) (Silicon Dioxide (SiO2) with Iron Oxide impurities) — sedimentary

Jasper (Red-Brown)

Silicon Dioxide (SiO2) with Iron Oxide impurities

Jasper (Petrified Wood variant) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Ironstone Concretion (Limonite/Hematite Nodules) (Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)) — sedimentary

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Stromatolite (Jasper-replaced) (Fossilized Stromatolite (Cyanobacteria / Cryptozon / Silica SiO2)) — sedimentary

Stromatolite (Jasper-replaced)

Fossilized Stromatolite (Cyanobacteria / Cryptozon / Silica SiO2)

Quartz Geode (Silicon Dioxide (SiO2) within a secondary sedimentary structure) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

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

Grey and White Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (specifically Tan/Yellow Chert) (Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (specifically Tan/Yellow Chert)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

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

Chert (Flint Pebbles)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Quartz Variety) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Quartz Variety)

Microcrystalline Silica (SiO2)

Shale with Vein Infillings (Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.) — Sedimentary Rock

Shale with Vein Infillings

Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.

Sedimentary Rock