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

Likely weathered quartz-rich stone or fossil fragment (Indeterminate; possibly quartz-bearing sandstone, iron-stained quartz, or a fragmentary fossil) — mineral

Likely weathered quartz-rich stone or fossil fragment

Indeterminate; possibly quartz-bearing sandstone, iron-stained quartz, or a fragmentary fossil

Petrified Wood (Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)

Banded iron formation fragment (likely hematite–magnetite ironstone) (Banded iron formation; chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and microcrystalline quartz (SiO₂)) — sedimentary

Banded iron formation fragment (likely hematite–magnetite ironstone)

Banded iron formation; chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and microcrystalline quartz (SiO₂)

Granite (Granite) — Igneous

Granite

Granite

Rounded iron-stained quartzite or sandstone pebble (Quartzite, predominantly SiO₂, with iron-oxide staining) — metamorphic

Rounded iron-stained quartzite or sandstone pebble

Quartzite, predominantly SiO₂, with iron-oxide staining

Weathered iron-rich rock, likely laterite or ironstone (Ferruginous laterite/ironstone, composed mainly of goethite (FeO(OH)), hematite (Fe₂O₃), and clay minerals) — sedimentary

Weathered iron-rich rock, likely laterite or ironstone

Ferruginous laterite/ironstone, composed mainly of goethite (FeO(OH)), hematite (Fe₂O₃), and clay minerals

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Siltstone (Siltstone (composed of clastic quartz and feldspar grains)) — sedimentary

Siltstone

Siltstone (composed of clastic quartz and feldspar grains)

Siltstone (Siltstone (composed of microscopic quartz and clay minerals)) — sedimentary

Siltstone

Siltstone (composed of microscopic quartz and clay minerals)

Sandstone (likely Quartzose Sandstone pebble) (Arenite (primarily SiO2)) — sedimentary

Sandstone (likely Quartzose Sandstone pebble)

Arenite (primarily SiO2)

Quartzite pebble (Quartzite (SiO2)) — metamorphic

Quartzite pebble

Quartzite (SiO2)

Quartzite (Quartzite (composed primarily of SiO2)) — metamorphic

Quartzite

Quartzite (composed primarily of SiO2)

Bull Quartz (White Quartz) (Silicon Dioxide (SiO2)) — mineral

Bull Quartz (White Quartz)

Silicon Dioxide (SiO2)

Asphalt (Aggregate) (Bituminous macadam / Concrete Aggregate) — sedimentary

Asphalt (Aggregate)

Bituminous macadam / Concrete Aggregate

Rhinestone (or glass crystal) (Silicon dioxide (if glass) / Various) — Mineral/gemstone imitation

Rhinestone (or glass crystal)

Silicon dioxide (if glass) / Various

Mineral/gemstone imitation

Petrified Wood (Silicified wood (primarily SiO2 - Silicon Dioxide/Quartz)) — metamorphic

Petrified Wood

Silicified wood (primarily SiO2 - Silicon Dioxide/Quartz)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Serpentinite (likely) (Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relic olivine/pyroxene) — metamorphic

Serpentinite (likely)

Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and relic olivine/pyroxene

Jasper (likely red/brown jasper) (Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides) — mineral

Jasper (likely red/brown jasper)

Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides

Likely tumbled jasper or iron-stained quartzite (Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions) — metamorphic

Likely tumbled jasper or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions

Petrified Wood / Fossilized Wood (Silicified Wood (Silicon Dioxide - SiO2)) — fossil

Petrified Wood / Fossilized Wood

Silicified Wood (Silicon Dioxide - SiO2)

Turquoise bead bracelet (Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O) — mineral

Turquoise bead bracelet

Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

Diamond (or diamond simulant) (C) — gemstone

Diamond (or diamond simulant)

C

Jadeite (Jade) (NaAlSi2O6 (Sodium Aluminum Silicate)) — metamorphic

Jadeite (Jade)

NaAlSi2O6 (Sodium Aluminum Silicate)

Granite or Pegmatite in host rock (Granitoid / Felsic Intrusive Rock) — Igneous

Granite or Pegmatite in host rock

Granitoid / Felsic Intrusive Rock

Greenstone (Epidosite) (Epidosite (Metamorphosed Basalt/Diabase)) — metamorphic

Greenstone (Epidosite)

Epidosite (Metamorphosed Basalt/Diabase)

Milky quartz pebble (Quartz (silicon dioxide, SiO₂)) — mineral

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Diorite (Diorite (intermediate intrusive igneous rock)) — igneous

Diorite

Diorite (intermediate intrusive igneous rock)

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

Sandstone

Arenite (SiO2 based with mineral cement)

Chert (Quartz var.) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Quartz var.)

Silicon Dioxide (SiO2)

Sandstone (Arenite (Sedimentary rock comprising sand-sized grains)) — sedimentary

Sandstone

Arenite (Sedimentary rock comprising sand-sized grains)

Petrified Wood (Silicified Fossil) (Silicified Wood (SiO2)) — sedimentary

Petrified Wood (Silicified Fossil)

Silicified Wood (SiO2)

Chert (Jasper or Flint variant) (Chert (composed of microcrystalline quartz, SiO2)) — sedimentary

Chert (Jasper or Flint variant)

Chert (composed of microcrystalline quartz, SiO2)

Flint Pebble (Sedimentary cryptocrystalline quartz (SiO2)) — sedimentary

Flint Pebble

Sedimentary cryptocrystalline quartz (SiO2)

Carved Stone Turtle (Carved Soapstone and Quartz) — mineral

Carved Stone Turtle

Carved Soapstone and Quartz

Sandstone (Sandstone (Quartz-rich Arenite / SiO2)) — sedimentary

Sandstone

Sandstone (Quartz-rich Arenite / SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Diorite (Polished Tumble) (Diorite (Intermediate intrusive igneous rock)) — Igneous

Diorite (Polished Tumble)

Diorite (Intermediate intrusive igneous rock)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Slag (Industrial Glass Slag) (Amorphous Silicate Glass (often containing Al, Ca, Mg, and Ti oxides)) — Mineraloid (Industrial byproduct)

Slag (Industrial Glass Slag)

Amorphous Silicate Glass (often containing Al, Ca, Mg, and Ti oxides)

Mineraloid (Industrial byproduct)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Flint / Chert (Silicon dioxide (SiO2)) — sedimentary

Flint / Chert

Silicon dioxide (SiO2)