Rock Identifier

Category

Biogenic Material

Browse biogenic material specimens identified by the Rock Identifier community.

Learn about Biogenic Material in the encyclopedia

Peat

Diatomite

Dunite

Limonite

Diamond

Peacock Opal

Metarhyolite

Rhodochrosite

Shell Opal

Madagascar Opal

Lavender Obsidian

Electric Blue Obsidian

Green Fluorite with Galena (Calcium Fluoride (CaF2) with Lead Sulfide (PbS)) — mineral

Green Fluorite with Galena

Calcium Fluoride (CaF2) with Lead Sulfide (PbS)

Chalcedony Pebble / Rough Agate (Silicon Dioxide (SiO2)) — mineral

Chalcedony Pebble / Rough Agate

Silicon Dioxide (SiO2)

Quartz Pebble with Mineral Inclusions (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble with Mineral Inclusions

Silicon Dioxide (SiO2)

Sandstone (Sandstone (SiO2 dominated)) — sedimentary

Sandstone

Sandstone (SiO2 dominated)

Sandstone (Arenite (primarily Quartz and Feldspar composition)) — sedimentary

Sandstone

Arenite (primarily Quartz and Feldspar composition)

Milky Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Coquina or Fossiliferous Sandstone (Fossiliferous Calcarenite (CaCO3 with SiO2 inclusions)) — sedimentary

Coquina or Fossiliferous Sandstone

Fossiliferous Calcarenite (CaCO3 with SiO2 inclusions)

Siltstone (Siltstone (Detrital Sedimentary Rock)) — sedimentary

Siltstone

Siltstone (Detrital Sedimentary Rock)

Siltstone or Mudstone (Siltstone (composed primarily of silt-sized particles)) — sedimentary

Siltstone or Mudstone

Siltstone (composed primarily of silt-sized particles)

Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone (Arenite (SiO2 based with mineral cements)) — sedimentary

Sandstone

Arenite (SiO2 based with mineral cements)

Amethyst (Amethyst (Silicon Dioxide, SiO2 + Fe4+)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2 + Fe4+)

Red Sand / Ferruginous Sand (Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) impurities) — sedimentary

Red Sand / Ferruginous Sand

Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) impurities

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

River Stone (likely Quartzite or Limestone) (Silicon dioxide (SiO2) or Calcium carbonate (CaCO3)) — metamorphic

River Stone (likely Quartzite or Limestone)

Silicon dioxide (SiO2) or Calcium carbonate (CaCO3)

Serpentinite (Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3Si2O5(OH)4) — metamorphic

Serpentinite

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3Si2O5(OH)4

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Chert / Flint Pebble (Microcrystalline Silica (SiO2)) — sedimentary

Chert / Flint Pebble

Microcrystalline Silica (SiO2)

Sandstone (with Calcite or Silica veins) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with Calcite or Silica veins)

Clastic sedimentary rock (primarily SiO2)

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

Limestone (Fossiliferous)

Calcium Carbonate (CaCO3)

Gneissic Granite (Granite Gneiss) — metamorphic

Gneissic Granite

Granite Gneiss

Chert (Flint) with Limestone Coating (Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) cortex) — sedimentary

Chert (Flint) with Limestone Coating

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) cortex

Granite (Granite (Phaneritic intrusive igneous rock)) — igneous

Granite

Granite (Phaneritic intrusive igneous rock)

Sandstone (Weathered) (Arenite (typically SiO2 as quartz grains)) — sedimentary

Sandstone (Weathered)

Arenite (typically SiO2 as quartz grains)

Red Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Red Quartzite Pebble

Quartzite (SiO2)

Sandstone (likely Ferruginous) (Arenite with Iron Oxide cement) — sedimentary

Sandstone (likely Ferruginous)

Arenite with Iron Oxide cement

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Sandstone Pebble (Arenite) — sedimentary

Sandstone Pebble

Arenite

Sandstone (Arenite (specifically Quartz Arenite)) — sedimentary

Sandstone

Arenite (specifically Quartz Arenite)

Sandstone (Arenite (primarily Quartz-based)) — sedimentary

Sandstone

Arenite (primarily Quartz-based)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Quartzite Pebble (Metamorphic Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Metamorphic Quartzite (SiO2)

Sandstone (Arenite (clastic sedimentary rock)) — sedimentary

Sandstone

Arenite (clastic sedimentary rock)

Quartzite pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite pebble

Quartzite (primarily SiO2)

Fossiliferous Limestone (Carbonate sedimentary rock (CaCO3) with bioclasts) — sedimentary

Fossiliferous Limestone

Carbonate sedimentary rock (CaCO3) with bioclasts

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

Peridot (Olivine) (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot (Olivine)

Olivine ((Mg, Fe)2SiO4)

Sandstone (Arenite (Sandstone)) — sedimentary

Sandstone

Arenite (Sandstone)

Sandstone (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of SiO2)

Greenstone / Greenschist (Greenschist facies metamorphic rock) — metamorphic

Greenstone / Greenschist

Greenschist facies metamorphic rock

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

Chert Nodules

Chert (Silicon Dioxide, SiO2)

Basalt Pebble (Basalt (Mafic volcanic rock)) — igneous

Basalt Pebble

Basalt (Mafic volcanic rock)