Rock Identifier

Category

Organic (Non Geological)

Browse organic (non geological) specimens identified by the Rock Identifier community.

Black Obsidian (Volcanic Glass (SiO2)) — igneous

Black Obsidian

Volcanic Glass (SiO2)

Small pale rock fragment (Indeterminate; possibly quartz, calcite, or a weathered feldspar-rich fragment) — mineral

Small pale rock fragment

Indeterminate; possibly quartz, calcite, or a weathered feldspar-rich fragment

Polished leopard-skin jasper (Orbicular jasper; microcrystalline quartz/chalcedony (SiO₂) with iron-oxide inclusions) — mineral

Polished leopard-skin jasper

Orbicular jasper; microcrystalline quartz/chalcedony (SiO₂) with iron-oxide inclusions

Red faceted gemstone ring (Likely synthetic ruby or red spinel; exact identification requires testing) — gemstone

Red faceted gemstone ring

Likely synthetic ruby or red spinel; exact identification requires testing

Schist with Garnet inclusions (Garnet-mica-schist) — metamorphic

Schist with Garnet inclusions

Garnet-mica-schist

Weathered ironstone concretion (probable limonite/goethite nodule) (Limonite-goethite-rich iron-oxide concretion; chiefly FeO(OH)·nH₂O) — mineral

Weathered ironstone concretion (probable limonite/goethite nodule)

Limonite-goethite-rich iron-oxide concretion; chiefly FeO(OH)·nH₂O

Quartzite Pebble (Metamorphic Quartzite (predominantly SiO2)) — metamorphic

Quartzite Pebble

Metamorphic Quartzite (predominantly SiO2)

Ferruginous Sandstone Concretion (Ironstone Phosphorite) (Ferruginous Sandstone (variable Fe-oxide/hydroxide composition)) — sedimentary

Ferruginous Sandstone Concretion (Ironstone Phosphorite)

Ferruginous Sandstone (variable Fe-oxide/hydroxide composition)

Cullet Glass (Slag Glass) (Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities) — mineraloid

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (SiO2) with metallic oxide impurities

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Black Obsidian (Volcanic Glass (SiO2)) — igneous

Black Obsidian

Volcanic Glass (SiO2)

Tumbled blue stone, likely sodalite (Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂; identification uncertain from image alone) — mineral

Tumbled blue stone, likely sodalite

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂; identification uncertain from image alone

Ambergris (Geological/Organic Specimen) (Ambra grisea (Produced by Physeter macrocephalus)) — organic material

Ambergris (Geological/Organic Specimen)

Ambra grisea (Produced by Physeter macrocephalus)

organic material

Petrified Wood (Silicified wood (primarily Silicon Dioxide, SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Fossil bone or tooth fragment (Mineralized fossil vertebrate bone/tooth; exact taxon cannot be determined from the photograph) — fossil

Fossil bone or tooth fragment

Mineralized fossil vertebrate bone/tooth; exact taxon cannot be determined from the photograph

Synthetic Resin (Artificial Specimen) (Polyurethane or Polyester Resin) — mineraloid (man-made)

Synthetic Resin (Artificial Specimen)

Polyurethane or Polyester Resin

mineraloid (man-made)

Limonite (with goethite) (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)) — mineral

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Fossilized Plant or Tree Bark (Lepidodendron or Sigillaria (example genera)) — sedimentary

Fossilized Plant or Tree Bark

Lepidodendron or Sigillaria (example genera)

Likely bituminous coal (Coal, predominantly carbon-rich organic matter with variable maceral and mineral content) — sedimentary

Likely bituminous coal

Coal, predominantly carbon-rich organic matter with variable maceral and mineral content

Tumbled pale green aventurine or common green quartzite (Quartz, SiO₂, likely with fuchsite or chlorite inclusions) — mineral

Tumbled pale green aventurine or common green quartzite

Quartz, SiO₂, likely with fuchsite or chlorite inclusions

Chert (Jasper/Flint variant) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variant)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Chert (variations include Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (variations include Flint)

Silicon Dioxide (SiO2)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Black Jasper (Etched) (Silicon Dioxide (SiO2) with impurities) — mineral

Black Jasper (Etched)

Silicon Dioxide (SiO2) with impurities

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon Dioxide (SiO2)

Chert with Limestone matrix (Microcrystalline silica (SiO2) in Calcite (CaCO3) matrix) — sedimentary

Chert with Limestone matrix

Microcrystalline silica (SiO2) in Calcite (CaCO3) matrix

Cupronickel (on a 1981 Mexico 20 Pesos coin) (Copper-Nickel Alloy (Cu75Ni25)) — mineral

Cupronickel (on a 1981 Mexico 20 Pesos coin)

Copper-Nickel Alloy (Cu75Ni25)

Oak Wood (Wood Grain Pattern) (Quercus (genus)) — Organic (Non-rock)

Oak Wood (Wood Grain Pattern)

Quercus (genus)

Organic (Non-rock)

Obsidian (Volcanic Glass (70% or more SiO2)) — igneous

Obsidian

Volcanic Glass (70% or more SiO2)

Black Obsidian (Volcanic Glass (Silicon Dioxide with impurities)) — igneous

Black Obsidian

Volcanic Glass (Silicon Dioxide with impurities)

Man-made Blank Ammunition (Brass) (CuZn (Cartridge Brass - roughly 70% Copper, 30% Zinc)) — Anticrystalline / Synthetic Alloy

Man-made Blank Ammunition (Brass)

CuZn (Cartridge Brass - roughly 70% Copper, 30% Zinc)

Anticrystalline / Synthetic Alloy

Quartzite (Metamorphic Quartzite (SiO2)) — metamorphic

Quartzite

Metamorphic Quartzite (SiO2)

Black onyx or black agate bead bracelet (Microcrystalline quartz, chiefly chalcedony (SiO₂); commonly sold as black onyx, sometimes dyed black agate) — gemstone

Black onyx or black agate bead bracelet

Microcrystalline quartz, chiefly chalcedony (SiO₂); commonly sold as black onyx, sometimes dyed black agate

Chert (Flint variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Jasper (Silicon Dioxide (Microcrystalline Quartz, SiO2)) — sedimentary

Jasper

Silicon Dioxide (Microcrystalline Quartz, SiO2)

Jasper (Silicon dioxide (SiO2)) — sedimentary

Jasper

Silicon dioxide (SiO2)

Pyrite (Fool's Gold) (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Fossiliferous Rock (Invertebrate Fossil in Matrix) (Fossiliferous limestone or shaly matrix containing skeletal fossil remains) — fossil

Fossiliferous Rock (Invertebrate Fossil in Matrix)

Fossiliferous limestone or shaly matrix containing skeletal fossil remains

Pink Coral (Corallium rubrum (or related species, composed of calcium carbonate)) — gemstone

Pink Coral

Corallium rubrum (or related species, composed of calcium carbonate)