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

Drupa or Druzy Quartz on Geode Fragment (Crystalline Silicon Dioxide (SiO2)) — mineral

Drupa or Druzy Quartz on Geode Fragment

Crystalline Silicon Dioxide (SiO2)

Sandstone (with manganese staining) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with manganese staining)

Clastic sedimentary rock (primarily SiO2)

Sandstone (with potential Arkose/Lithic characteristics) (Arenite (Sedimentary rock composed of sand-sized grains)) — sedimentary

Sandstone (with potential Arkose/Lithic characteristics)

Arenite (Sedimentary rock composed of sand-sized grains)

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

Chert (Common Opal variant)

Microcrystalline Quartz (SiO2)

Pink-and-white quartz-rich rock, likely rose quartz or quartzite (Quartz (SiO₂), possibly rose-quartz-bearing quartzite; minor iron-oxide staining) — metamorphic

Pink-and-white quartz-rich rock, likely rose quartz or quartzite

Quartz (SiO₂), possibly rose-quartz-bearing quartzite; minor iron-oxide staining

Diamond (or Diamond Simulant) (Carbon (C)) — gemstone

Diamond (or Diamond Simulant)

Carbon (C)

Diamond (Native Carbon (C)) — gemstone

Diamond

Native Carbon (C)

Diamond (Carbon (C)) — gemstone

Diamond

Carbon (C)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Diamond (Cut Gemstone) (Carbon (C)) — gemstone

Diamond (Cut Gemstone)

Carbon (C)

Fossilized Shark Tooth (Anterior/Lateral) (Otodus megalodon or Carcharodon carcharias (fossilized)) — fossil

Fossilized Shark Tooth (Anterior/Lateral)

Otodus megalodon or Carcharodon carcharias (fossilized)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Diamond (Diamond (pure Carbon, C)) — mineral

Diamond

Diamond (pure Carbon, C)

Boulder Opal (Hydrated Silica (SiO2·nH2O)) — mineraloid

Boulder Opal

Hydrated Silica (SiO2·nH2O)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Limonite (Ironstone) (Limonite (mixture of hydrated iron(III) oxide-hydroxides)) — mineral

Limonite (Ironstone)

Limonite (mixture of hydrated iron(III) oxide-hydroxides)

Diamond (Carbon (C)) — gemstone

Diamond

Carbon (C)

Riverstone (Siltstone/Mudstone) (Siltstone) — sedimentary

Riverstone (Siltstone/Mudstone)

Siltstone

Petrified Rugose Coral (Horn Coral) (Order Rugosa (extinct coral)) — sedimentary

Petrified Rugose Coral (Horn Coral)

Order Rugosa (extinct coral)

Tumbled green aventurine (probable) (Quartz, SiO₂, with fuchsite mica inclusions) — mineral

Tumbled green aventurine (probable)

Quartz, SiO₂, with fuchsite mica inclusions

Sandstone (with concrete/human-made layer) (Clastic Sedimentary Rock (primarily Quartz/Feldspar grains)) — sedimentary

Sandstone (with concrete/human-made layer)

Clastic Sedimentary Rock (primarily Quartz/Feldspar grains)

Tumbled green aventurine (Quartz variety, mainly SiO₂ with fuchsite or other mica inclusions) — mineral

Tumbled green aventurine

Quartz variety, mainly SiO₂ with fuchsite or other mica inclusions

Flint (Microcrystalline quartz (SiO2)) — sedimentary

Flint

Microcrystalline quartz (SiO2)

Sedimentary Rock with Crafts (Pet Rock) (Sedimentary rock decorated with synthetic materials) — sedimentary

Sedimentary Rock with Crafts (Pet Rock)

Sedimentary rock decorated with synthetic materials

Chert (with Limestone/Dolomite host) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Limestone/Dolomite host)

Microcrystalline Quartz (SiO2)

Bumblebee Jasper (Calcite-bearing Volcanic Tuff containing Sulfur and Arsenic (Orpiment/Realgar)) — sedimentary

Bumblebee Jasper

Calcite-bearing Volcanic Tuff containing Sulfur and Arsenic (Orpiment/Realgar)

Scoria (Volcanic Rock) (Scoria (often basaltic scoria)) — Igneous

Scoria (Volcanic Rock)

Scoria (often basaltic scoria)

Agate (Silicon Dioxide (Chalcedony), SiO2) — gemstone

Agate

Silicon Dioxide (Chalcedony), SiO2

Sandstone (Tumbled / Rounded) (Sedimentary Rock (Quartz arenite)) — sedimentary

Sandstone (Tumbled / Rounded)

Sedimentary Rock (Quartz arenite)

Flint (SiO2 (Cryptocrystalline Quartz)) — sedimentary

Flint

SiO2 (Cryptocrystalline Quartz)

Flint (SiO2 (Microcrystalline Quartz)) — sedimentary

Flint

SiO2 (Microcrystalline Quartz)

Flint (or Chert) (Microcrystalline quartz (SiO2)) — sedimentary

Flint (or Chert)

Microcrystalline quartz (SiO2)

Travertine (Tufa) (Travertine (Aragonite/Calcite form of Calcium Carbonate, CaCO3)) — sedimentary

Travertine (Tufa)

Travertine (Aragonite/Calcite form of Calcium Carbonate, CaCO3)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Fossil Snail (Gastropoda (fossilized)) — fossil

Fossil Snail

Gastropoda (fossilized)

Fossil Snail (Gastropoda (fossilized)) — fossil

Fossil Snail

Gastropoda (fossilized)

Mammoth Molar Fossil (Mammuthus primigenius (Tooth fragment)) — fossil

Mammoth Molar Fossil

Mammuthus primigenius (Tooth fragment)

Jasper (Silicon dioxide (SiO2) with impurities, microcrystalline quartz) — sedimentary

Jasper

Silicon dioxide (SiO2) with impurities, microcrystalline quartz

Goethite / Limonite Concretion (Iron Hydroxide Oxide (FeO(OH))) — sedimentary

Goethite / Limonite Concretion

Iron Hydroxide Oxide (FeO(OH))

Chert (Flint) Nodule (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint) Nodule

Microcrystalline Quartz (SiO2)

Chert (Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Cryptocrystalline Quartz (SiO2)