Rock Identifier

Category

Organic (Geological Interest)

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

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Greisen (Quartz-Muscovite-Turretine Rock) (Greisen) — Metamorphic Rock

Greisen (Quartz-Muscovite-Turretine Rock)

Greisen

Metamorphic Rock

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

Petrified Wood (Silicified Wood)

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Silty Shale or Mudstone (Siltstone/Mudstone (Clastic Sedimentary Rock)) — sedimentary

Silty Shale or Mudstone

Siltstone/Mudstone (Clastic Sedimentary Rock)

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

Chert (Cherty Shale / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert Nodule (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodule

Microcrystalline Quartz (SiO2)

Moqui Marble (Shaman Stone) (Iron Oxide Concretion (composed primarily of Quartz sand with Hematite/Goethite shell)) — sedimentary

Moqui Marble (Shaman Stone)

Iron Oxide Concretion (composed primarily of Quartz sand with Hematite/Goethite shell)

Quartz (on matrix) (Quartz (Silicon Dioxide, SiO₂)) — Mineral

Quartz (on matrix)

Quartz (Silicon Dioxide, SiO₂)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Fossilized Coral (Petoskey Stone or Tabulate Coral) (Scleractinia or Tabulata (CaCO3 - Calcium Carbonate)) — fossil

Fossilized Coral (Petoskey Stone or Tabulate Coral)

Scleractinia or Tabulata (CaCO3 - Calcium Carbonate)

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

Brick (Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)) — Man-made material (constructed)

Brick

Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)

Man-made material (constructed)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

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

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

Fossiliferous Brachiopod in Shale (Brachiopoda (Phylum) preserved in Carbonaceous Shale) — sedimentary

Fossiliferous Brachiopod in Shale

Brachiopoda (Phylum) preserved in Carbonaceous Shale

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood (SiO2)) — metamorphic

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood (SiO2)

Chert (Jasper variation) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper variation)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (White/Light Tan) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White/Light Tan)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Nodular) (Chert (SiO2 - Microcrystalline Quartz)) — sedimentary

Chert (Nodular)

Chert (SiO2 - Microcrystalline Quartz)

Chert Pebble with Quartz Veins (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble with Quartz Veins

Microcrystalline Quartz (SiO2)

Chert (specifically Tan/Brown Chert) (Chert (SiO2)) — sedimentary

Chert (specifically Tan/Brown Chert)

Chert (SiO2)

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

Travertine (Tufa)

Chemical Limestone (CaCO3)

Petrified Wood (Silicified Wood (primarily Quartz / Chalcedony: SiO2)) — metamorphic

Petrified Wood

Silicified Wood (primarily Quartz / Chalcedony: SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Banded calcite (travertine or calcite-rich carbonate) (Calcite, CaCO₃; likely banded travertine or recrystallized limestone) — sedimentary

Banded calcite (travertine or calcite-rich carbonate)

Calcite, CaCO₃; likely banded travertine or recrystallized limestone

Quartz Geode in Chert/Limestone Matrix (Silicon Dioxide (SiO2) within Sedimentary Host Rock) — sedimentary

Quartz Geode in Chert/Limestone Matrix

Silicon Dioxide (SiO2) within Sedimentary Host Rock

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

Picture Jasper

Silicon Dioxide (SiO2) with iron oxide and organic impurities

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

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (Septarian or Nodular variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Septarian or Nodular variety)

Microcrystalline Quartz (SiO2)

Chert (and Jasper variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (and Jasper variety)

Microcrystalline Quartz (SiO2)

Limestone (Weathered) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Weathered)

Calcium Carbonate (CaCO3)

Petrified Wood (Petrified Wood (Silicified Wood)) — fossil

Petrified Wood

Petrified Wood (Silicified Wood)

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

Chert (Chert Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Iron-stained River Cobble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained River Cobble)

Microcrystalline Quartz (SiO2)

Graphite (Graphite (C)) — mineral

Graphite

Graphite (C)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)