Rock Identifier

Category

Organic (Non Rock)

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

Fossiliferous Limestone (Limestone with fossil inclusions (CaCO3)) — sedimentary

Fossiliferous Limestone

Limestone with fossil inclusions (CaCO3)

Granite (Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase)) — igneous

Granite

Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase)

Gneiss (specifically Granitic Gneiss) (Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)) — metamorphic

Gneiss (specifically Granitic Gneiss)

Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)

Sandstone (Pebble) (Sandstone (arenite, arkose, wacke depending on composition)) — sedimentary

Sandstone (Pebble)

Sandstone (arenite, arkose, wacke depending on composition)

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Chert (specifically Tan/Gray Chert) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (specifically Tan/Gray Chert)

Microcrystalline quartz (SiO2)

Granite (Granite (Mainly Quartz, Feldspar, and Mica)) — Igneous

Granite

Granite (Mainly Quartz, Feldspar, and Mica)

Ironstone (likely Ferruginous Siltstone/Sandstone) (Ferruginous sedimentary rock (FeOx-rich clastic)) — sedimentary

Ironstone (likely Ferruginous Siltstone/Sandstone)

Ferruginous sedimentary rock (FeOx-rich clastic)

Quartz (Float/Abraded) (Quartz (SiO₂)) — Mineral

Quartz (Float/Abraded)

Quartz (SiO₂)

Greenstone (Epidote/Chlorite-rich Metabasalt) (Greenschist / Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))) — metamorphic

Greenstone (Epidote/Chlorite-rich Metabasalt)

Greenschist / Epidosite (Ca2(Al,Fe)3(SiO4)3(OH))

Laterite (iron-rich nodule, possibly Bauxite as a subtype) (Laterite (composed of various minerals including goethite, hematite, gibbsite, etc.)) — Sedimentary

Laterite (iron-rich nodule, possibly Bauxite as a subtype)

Laterite (composed of various minerals including goethite, hematite, gibbsite, etc.)

Chert (Nodular) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Nodular)

Microcrystalline Silica (SiO2)

Quartz Vein in Metamorphic Rock (Silicon Dioxide (SiO2) within Metasedimentary host) — metamorphic

Quartz Vein in Metamorphic Rock

Silicon Dioxide (SiO2) within Metasedimentary host

Green Aventurine (Silicon dioxide with Fuscite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)) — mineral

Green Aventurine

Silicon dioxide with Fuscite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Fossilized Coral (Petoskey-like or Favosites) (Anthozoa (Fossilized Coral)) — sedimentary

Fossilized Coral (Petoskey-like or Favosites)

Anthozoa (Fossilized Coral)

Quartz / Chert (Silicon Dioxide (SiO2)) — Mineral / Sedimentary

Quartz / Chert

Silicon Dioxide (SiO2)

Mineral / Sedimentary

Hag Stone (Perforated Chert (Microcrystalline Silica, SiO2)) — sedimentary

Hag Stone

Perforated Chert (Microcrystalline Silica, SiO2)

Serpentine (Serpentinite (rock) containing serpentine minerals (e.g., Antigorite, Lizardite, Chrysotile)) — Metamorphic rock

Serpentine

Serpentinite (rock) containing serpentine minerals (e.g., Antigorite, Lizardite, Chrysotile)

Metamorphic rock

Limestone (Calcareous sedimentary rock (primarily CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (primarily CaCO3)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

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

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz Vein in Host Rock (Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix) — igneous

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix

Chalk / Sedimentary Limestone (Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock) — sedimentary

Chalk / Sedimentary Limestone

Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock

Chert (often called Flint when dark) (Sedimentary cryptocrystalline quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Sedimentary cryptocrystalline quartz (SiO2)

Granite (Phaneritic plutonic rock (Felsic)) — igneous

Granite

Phaneritic plutonic rock (Felsic)

Quartz Vein in Host Rock (Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix) — Metamorphic or Igneous (context dependent)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Metamorphic or Igneous (context dependent)

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

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Tan/Grey variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Tan/Grey variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Hag Stone (Porous sedimentary rock (typically Flint, Chert, or Sandstone) with naturally occurring holes) — sedimentary

Hag Stone

Porous sedimentary rock (typically Flint, Chert, or Sandstone) with naturally occurring holes

Chert (and Limestone) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Limestone)

Silicon Dioxide (SiO2)

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

Chert (and Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Almandine Garnet in Matrix (Almandine, Fe3Al2(SiO4)3) — metamorphic

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

Porphyritic Rhyolite (Rhyolite (Porphyritic texture)) — igneous

Porphyritic Rhyolite

Rhyolite (Porphyritic texture)

Asphalt (Bituminous Slate/Sandstone) (Asphaltum / Bituminous Rock) — sedimentary

Asphalt (Bituminous Slate/Sandstone)

Asphaltum / Bituminous Rock

Laterite (Laterite (primarily composed of hydrated oxides of iron and aluminum)) — Sedimentary Rock (as a residual soil/rock, it's often considered a type of sedimentary rock due to its formation from weathering, though it can cross into soil science)

Laterite

Laterite (primarily composed of hydrated oxides of iron and aluminum)

Sedimentary Rock (as a residual soil/rock, it's often considered a type of sedimentary rock due to its formation from weathering, though it can cross into soil science)

Quartz (variety of colors) (SiO2 (Silicon Dioxide)) — Mineral

Quartz (variety of colors)

SiO2 (Silicon Dioxide)

Chert (often called Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)

Milky Quartz (Gold-bearing Prospecting Specimen) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Gold-bearing Prospecting Specimen)

Silicon Dioxide (SiO2)

Conglomerate (Conglomerate (a clastic sedimentary rock)) — Sedimentary

Conglomerate

Conglomerate (a clastic sedimentary rock)

Chert (Jasper variety) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper variety)

Silicon dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Flint Nodules)

Silicon Dioxide (SiO2)