Rock Identifier

Category

Organic (Geological Relative)

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

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

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (specifically Green Chert/Jasper) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — sedimentary

Chert (specifically Green Chert/Jasper)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (Red/Pink Jasper subtype) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Red/Pink Jasper subtype)

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Chert (primarily Microcrystalline Quartz, SiO2)) — sedimentary

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)

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

Pyrite in Shale

Iron Sulfide (FeS2) in Argillaceous Shale

River Stone (Chert/Siltstone) (Cryptocrystalline Quartz (SiO2) with trace impurities) — sedimentary

River Stone (Chert/Siltstone)

Cryptocrystalline Quartz (SiO2) with trace impurities

Pyritic Mudstone (Argillaceous rock (FeS2)) — sedimentary

Pyritic Mudstone

Argillaceous rock (FeS2)

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

Petrified Wood

Silicified wood (primarily SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2 - Quartz/Chalcedony replacement)) — Mineral / Fossil

Petrified Wood

Silicified Wood (SiO2 - Quartz/Chalcedony replacement)

Mineral / Fossil

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement) SiO2

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

Petrified Wood

Silicified Wood (primarily SiO₂)

Pyrite (Pyrite (FeS2)) — Mineral

Pyrite

Pyrite (FeS2)

Flint (chert), likely brown flint (Microcrystalline quartz/chalcedony (SiO₂)) — sedimentary

Flint (chert), likely brown flint

Microcrystalline quartz/chalcedony (SiO₂)

Travertine / Tufa (Calcium Carbonate (CaCO3)) — sedimentary

Travertine / Tufa

Calcium Carbonate (CaCO3)

Quartz Geode (Silicon Dioxide (SiO2) in sedimentary host rock) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2) in sedimentary host rock

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Manganese-coated Sandstone (Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)) — sedimentary

Manganese-coated Sandstone

Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)

Chert Nodule (Microcrystalline Silica (SiO2)) — sedimentary

Chert Nodule

Microcrystalline Silica (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Chert (or Flint) (Chert (Sedimentary Cryptocrystalline Sio2)) — sedimentary

Chert (or Flint)

Chert (Sedimentary Cryptocrystalline Sio2)

Petrified Wood (Silicified wood (principally Silicon Dioxide, SiO2)) — sedimentary

Petrified Wood

Silicified wood (principally Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Lazulite (Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2) — mineral

Lazulite

Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2

Liesegang Ring Siltstone (Siltstone with iron oxide Liesegang bands) — sedimentary

Liesegang Ring Siltstone

Siltstone with iron oxide Liesegang bands

Pearls (Pearl: biomineralized aragonite (CaCO₃) and conchiolin) — gemstone

Pearls

Pearl: biomineralized aragonite (CaCO₃) and conchiolin

Biological Bone (Patella/Knee) (Patella (part of the Human Skeletal System)) — Organic Structure (Not a Rock)

Biological Bone (Patella/Knee)

Patella (part of the Human Skeletal System)

Organic Structure (Not a Rock)

Limestone with Lichen/Moss (Calcium Carbonate (CaCO3)) — sedimentary

Limestone with Lichen/Moss

Calcium Carbonate (CaCO3)

Green Chert (Silicon Dioxide (SiO2)) — sedimentary

Green Chert

Silicon Dioxide (SiO2)

Mixed Quartz and Jasper Pebbles (Silicon Dioxide (SiO2)) — Mineral

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

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

Travertine (Tufa)

Chemical Limestone (CaCO3)

Dark Igneous Rock (Likely Basalt or Diabase) (Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.) — Igneous

Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

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

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide)

Moss Agate (Silicon Dioxide with inclusions (SiO2)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2)

Petrified Wood (Silicified Wood (SiO2 permineralization)) — fossil

Petrified Wood

Silicified Wood (SiO2 permineralization)