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

Veined Pebble (Septarian or Quartz-Veined Chert/Basalt) (Silicon Dioxide (SiO2) veins in matrix) — sedimentary

Veined Pebble (Septarian or Quartz-Veined Chert/Basalt)

Silicon Dioxide (SiO2) veins in matrix

Red Sandstone (Sandstone (hematitic/iron-rich quartzite or arenite)) — sedimentary

Red Sandstone

Sandstone (hematitic/iron-rich quartzite or arenite)

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 (Arenite (SiO2 principal composition)) — sedimentary

Sandstone

Arenite (SiO2 principal composition)

Sandstone (lithic/quartz variant) (Clastic sedimentary rock (SiO2 predominant)) — sedimentary

Sandstone (lithic/quartz variant)

Clastic sedimentary rock (SiO2 predominant)

Prasiolite (Green Quartz) / Sea Glass Amalgam (SiO2 (Silicon Dioxide)) — mineral

Prasiolite (Green Quartz) / Sea Glass Amalgam

SiO2 (Silicon Dioxide)

Siltstone Pebble (Siltstone (primarily SiO2 with Al2O3)) — sedimentary

Siltstone Pebble

Siltstone (primarily SiO2 with Al2O3)

Sandstone (Arenite (SiO2 composition dominant)) — sedimentary

Sandstone

Arenite (SiO2 composition dominant)

Jasper (Green Jasper/River Stone) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper (Green Jasper/River Stone)

Silicon Dioxide (SiO2) with impurities

Yellow Jasper (Silicon Dioxide (SiO2) - variety Jasper) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) - variety Jasper

Sandstone (Arenite (mainly SiO2 with varying cements)) — sedimentary

Sandstone

Arenite (mainly SiO2 with varying cements)

Sandstone (Arenite (SiO2 principal)) — sedimentary

Sandstone

Arenite (SiO2 principal)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Sandstone (with Chert/Quartzite) (Arenite (SiO2 primarily)) — sedimentary

Sandstone (with Chert/Quartzite)

Arenite (SiO2 primarily)

Ammonite Fossil (Ammonoidea (primarily composed of Calcite, CaCO3)) — sedimentary

Ammonite Fossil

Ammonoidea (primarily composed of Calcite, CaCO3)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Fire Opal (in Matrix) (Hydrated Silica (SiO2·nH2O)) — mineral

Fire Opal (in Matrix)

Hydrated Silica (SiO2·nH2O)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Sandstone (lithic wacke/conglomerate mix) (Clastic Sedimentary Rock (SiO2 with lithic fragments)) — sedimentary

Sandstone (lithic wacke/conglomerate mix)

Clastic Sedimentary Rock (SiO2 with lithic fragments)

Sandstone (Quartzite-rich) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Quartzite-rich)

Clastic sedimentary rock (primarily SiO2)

Marble (Recrystallized Calcite (CaCO3)) — metamorphic

Marble

Recrystallized Calcite (CaCO3)

Glacial Erratic (Sandstone/Quartzite) (Glacial Erratic specimen (likely Orthoquartzite or Feldspathic Sandstone)) — sedimentary or metamorphic

Glacial Erratic (Sandstone/Quartzite)

Glacial Erratic specimen (likely Orthoquartzite or Feldspathic Sandstone)

sedimentary or metamorphic

Siltstone Pebble (Siltstone) — sedimentary

Siltstone Pebble

Siltstone

Sandstone with Manganese Dendrites (Arenite (mostly SiO2) with Manganese Oxide inclusions (MnO2)) — sedimentary

Sandstone with Manganese Dendrites

Arenite (mostly SiO2) with Manganese Oxide inclusions (MnO2)

Marble (polished) (Recrystallized Calcite (CaCO3)) — metamorphic

Marble (polished)

Recrystallized Calcite (CaCO3)

Olivine in Basalt (Peridotite / Forsterite ((Mg,Fe)2SiO4)) — igneous

Olivine in Basalt

Peridotite / Forsterite ((Mg,Fe)2SiO4)

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

Sandstone (likely Quartz Sandstone)

Arenite (composed primarily of SiO2)

Sunstone ((Ca,Na)(Al,Si)4O8 (Oligoclase or Andesine)) — mineral

Sunstone

(Ca,Na)(Al,Si)4O8 (Oligoclase or Andesine)

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

Sandstone

Clastic sedimentary rock (primarily SiO2)

Geode with Quartz/Chalcedony (Silicon Dioxide (SiO2)) — sedimentary

Geode with Quartz/Chalcedony

Silicon Dioxide (SiO2)

Amazonite (Microcline (KAlSi3O8) with trace lead (Pb)) — mineral

Amazonite

Microcline (KAlSi3O8) with trace lead (Pb)

Sandstone (likely Fossiliferous) (Arenite / Fossiliferous Sandstone (SiO2 composition)) — sedimentary

Sandstone (likely Fossiliferous)

Arenite / Fossiliferous Sandstone (SiO2 composition)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Limestone (Cliff Formation) (Limestone (predominantly CaCO3 as calcite)) — Sedimentary

Limestone (Cliff Formation)

Limestone (predominantly CaCO3 as calcite)

Polished quartz-rich pebble, possibly jasper or quartzite (Quartzite or chalcedony-bearing jasper; predominantly SiO₂) — metamorphic

Polished quartz-rich pebble, possibly jasper or quartzite

Quartzite or chalcedony-bearing jasper; predominantly SiO₂

Chert (Common Opal variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Common Opal variant)

Microcrystalline Quartz (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Diamond (C (Carbon)) — gemstone

Diamond

C (Carbon)

Black Granite (Basalt or Gabbro) (Mafic Igneous Rock (primarily Plagioclase and Pyroxene)) — igneous

Black Granite (Basalt or Gabbro)

Mafic Igneous Rock (primarily Plagioclase and Pyroxene)