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

Quartz pebble (Silicon dioxide (SiO2)) — mineral

Quartz pebble

Silicon dioxide (SiO2)

Sandstone (Quartzose Sandstone) (Clastic Sedimentary Rock - Arenite) — sedimentary

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock - Arenite

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

Sandstone (Red)

Arenite (composed primarily of SiO2)

Sandstone (Stream-rounded Cobble) (Arenite (composed primarily of SiO2, Silica)) — sedimentary

Sandstone (Stream-rounded Cobble)

Arenite (composed primarily of SiO2, Silica)

Sandstone (Banded) (Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide staining)) — sedimentary

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2 with Iron Oxide staining)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (Ferruginous) (Arenite (primarily SiO2 with iron oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide cement)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Sandstone (likely Ferruginous) (Arenite (SiO2 with iron oxide impurities)) — sedimentary

Sandstone (likely Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Sandstone (Arenite (primarily Quartz Arenite)) — sedimentary

Sandstone

Arenite (primarily Quartz Arenite)

Sandstone (Ferruginous) (Arenite (Fe2O3 enriched)) — sedimentary

Sandstone (Ferruginous)

Arenite (Fe2O3 enriched)

Sandstone (likely Siltstone or fine-grained Sandstone) (Sedimentary Rock (Clastic)) — sedimentary

Sandstone (likely Siltstone or fine-grained Sandstone)

Sedimentary Rock (Clastic)

Moss Agate (Chalcedony (SiO2) with inclusions of manganese or iron oxides) — mineral

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Sandstone (Arenite (Clastic Sedimentary Rock)) — sedimentary

Sandstone

Arenite (Clastic Sedimentary Rock)

Quartzite and Sandstone Pebbles (Silicon dioxide (SiO2)) — metamorphic and sedimentary

Quartzite and Sandstone Pebbles

Silicon dioxide (SiO2)

metamorphic and sedimentary

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Peridotite (Peridotite (primarily Olivine and Pyroxene)) — igneous

Peridotite

Peridotite (primarily Olivine and Pyroxene)

Sandstone (Wonderstone) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Wonderstone)

Clastic Sedimentary Rock (primarily SiO2)

Yellow Quartzite (River Pebble) (Quartzite (primarily Silicon Dioxide, SiO2)) — metamorphic

Yellow Quartzite (River Pebble)

Quartzite (primarily Silicon Dioxide, SiO2)

Sandstone (with Iron Staining) (Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

Sandstone (Quartz Arenite) (Sandstone (dominated by SiO2 quartz grains)) — sedimentary

Sandstone (Quartz Arenite)

Sandstone (dominated by SiO2 quartz grains)

Quartzite Pebble (Quartzite (mostly SiO2)) — metamorphic

Quartzite Pebble

Quartzite (mostly SiO2)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Sandstone (Calcareous Sandstone) (Calcareous Sandstone (primarily SiO2 with CaCO3 cement)) — sedimentary

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Sandstone (likely Ferruginous) (Sandstone (SiO2 with iron oxides)) — sedimentary

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Quartz Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Sandstone (likely Arkose or Quartz Sandstone) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (likely Arkose or Quartz Sandstone)

Clastic sedimentary rock (primarily SiO2)

Siltstone Pebble (Siltstone (fine-grained siliciclastic sedimentary rock)) — sedimentary

Siltstone Pebble

Siltstone (fine-grained siliciclastic sedimentary rock)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Coquina Limestone (Coquina (Calcium Carbonate, CaCO3)) — sedimentary

Coquina Limestone

Coquina (Calcium Carbonate, CaCO3)

Clay (as a rock-forming material) (Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)) — Mineral

Clay (as a rock-forming material)

Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)

Milky quartz with dark host-rock inclusions (Quartz (SiO₂), likely in a granitic or metamorphic matrix) — mineral

Milky quartz with dark host-rock inclusions

Quartz (SiO₂), likely in a granitic or metamorphic matrix

Likely quartz-rich mineral fragment (Quartz (SiO₂), possibly iron-stained or included quartz) — mineral

Likely quartz-rich mineral fragment

Quartz (SiO₂), possibly iron-stained or included quartz

Geode (Unopened) (Silica-rich Concretion (primarily SiO2)) — sedimentary

Geode (Unopened)

Silica-rich Concretion (primarily SiO2)

Textile (Upholstery Fabric) (Woven Polyethylene/Polyester or Cotton Blend) — Synthetic or Natural Fiber

Textile (Upholstery Fabric)

Woven Polyethylene/Polyester or Cotton Blend

Synthetic or Natural Fiber

Tumbled black stone, likely basalt (Basalt; fine-grained plagioclase–pyroxene rock, possibly with magnetite) — igneous

Tumbled black stone, likely basalt

Basalt; fine-grained plagioclase–pyroxene rock, possibly with magnetite

Granite (Felsic intrusive igneous rock) — igneous

Granite

Felsic intrusive igneous rock

Polished brecciated jasper (Jasper (microcrystalline quartz, SiO₂), likely brecciated and iron-stained) — metamorphic

Polished brecciated jasper

Jasper (microcrystalline quartz, SiO₂), likely brecciated and iron-stained

Banded agate (likely carnelian/chalcedony) (Microcrystalline quartz, SiO₂; iron-stained chalcedony) — mineral

Banded agate (likely carnelian/chalcedony)

Microcrystalline quartz, SiO₂; iron-stained chalcedony

Weathered fossiliferous limestone fragment, possibly fossil coral or shell material (Indeterminate carbonate fossil in calcitic limestone; likely composed mainly of calcite (CaCO₃), but species identification is not possible from this image alone) — fossil

Weathered fossiliferous limestone fragment, possibly fossil coral or shell material

Indeterminate carbonate fossil in calcitic limestone; likely composed mainly of calcite (CaCO₃), but species identification is not possible from this image alone