Rock Identifier

Category

Organic (Non Geological)

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

Likely coal (possibly anthracite) (Coal, composed chiefly of carbon-rich organic matter; rank cannot be confirmed from the photograph) — sedimentary

Likely coal (possibly anthracite)

Coal, composed chiefly of carbon-rich organic matter; rank cannot be confirmed from the photograph

Small dark pebble, likely basalt or iron-rich rock (Uncertain from image; possibly fine-grained basalt (mafic silicate rock)) — igneous

Small dark pebble, likely basalt or iron-rich rock

Uncertain from image; possibly fine-grained basalt (mafic silicate rock)

Red Coral (Precious Coral) (Corallium rubrum (Calcium Carbonate, CaCO3)) — sedimentary

Red Coral (Precious Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

Quartz Geode with Calcite (Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)) — Mineral/Geode

Quartz Geode with Calcite

Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)

Quartzite (Metamorphic Quartzite (SiO2)) — metamorphic

Quartzite

Metamorphic Quartzite (SiO2)

Blue polished cabochon, likely dyed agate or chalcedony (Chalcedony (microcrystalline quartz, SiO₂); exact material cannot be confirmed from the image) — gemstone

Blue polished cabochon, likely dyed agate or chalcedony

Chalcedony (microcrystalline quartz, SiO₂); exact material cannot be confirmed from the image

Concretion or weathered iron-rich rock (Likely limonite/goethite-rich concretion; exact identification requires testing) — sedimentary

Concretion or weathered iron-rich rock

Likely limonite/goethite-rich concretion; exact identification requires testing

Fossil shell fragment (likely brachiopod or bivalve) (Indeterminate fossilized carbonate shell; likely Brachiopoda or Bivalvia) — fossil

Fossil shell fragment (likely brachiopod or bivalve)

Indeterminate fossilized carbonate shell; likely Brachiopoda or Bivalvia

Pearls (likely freshwater cultured pearls) (Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin) — gemstone

Pearls (likely freshwater cultured pearls)

Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin

Chert (Chert (SiO2)) — sedimentary

Chert

Chert (SiO2)

Limestone (or Calcite Pebble) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (or Calcite Pebble)

Calcium Carbonate (CaCO3)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Chert Pebble (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble

Microcrystalline Quartz (SiO2)

Banded Chert (Silicon Dioxide (SiO2)) — sedimentary

Banded Chert

Silicon Dioxide (SiO2)

Quartzite (Metamorphic Quartzite) — metamorphic

Quartzite

Metamorphic Quartzite

Polished ornamental jasper (likely Peanut Wood or similar brecciated jasper) (Microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and clay inclusions) — mineral

Polished ornamental jasper (likely Peanut Wood or similar brecciated jasper)

Microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and clay inclusions

Mother of Pearl and Onyx (Aragonite (Mother of Pearl) and Chalcedony (Onyx)) — mineral

Mother of Pearl and Onyx

Aragonite (Mother of Pearl) and Chalcedony (Onyx)

Pink Opal (Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions) — Mineraloid

Pink Opal

Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions

Green glassy mineral specimen, likely rough emerald or green fluorite (Tentatively beryl (Be₃Al₂Si₆O₁₈), emerald variety; synthetic/man-made glass cannot be excluded from the photograph) — mineral

Green glassy mineral specimen, likely rough emerald or green fluorite

Tentatively beryl (Be₃Al₂Si₆O₁₈), emerald variety; synthetic/man-made glass cannot be excluded from the photograph

N/A (Non-Geological Object) — N/A

N/A (Non-Geological Object)

Faceted purple-blue beads, likely synthetic glass or treated gemstone (Indeterminate; possible synthetic corundum, synthetic spinel, or dyed quartz (SiO₂)) — gemstone

Faceted purple-blue beads, likely synthetic glass or treated gemstone

Indeterminate; possible synthetic corundum, synthetic spinel, or dyed quartz (SiO₂)

Stainless Steel Spoon (Iron-Chromium Alloy (Fe + Cr + Ni)) — mineral-based human-made alloy

Stainless Steel Spoon

Iron-Chromium Alloy (Fe + Cr + Ni)

mineral-based human-made alloy

Quartz-veined Limestone (Sedimentary limestone with quartz/calcite veinlets) — sedimentary

Quartz-veined Limestone

Sedimentary limestone with quartz/calcite veinlets

Shale or Mudstone (Based on appearance) (Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)) — Sedimentary

Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

Pearl-and-gemstone insect brooch (Pearl: nacre (aragonite, CaCO₃); colored stones are likely synthetic or natural corundum/spinel/glass, not determinable from the image) — gemstone

Pearl-and-gemstone insect brooch

Pearl: nacre (aragonite, CaCO₃); colored stones are likely synthetic or natural corundum/spinel/glass, not determinable from the image

Orbicular granite (likely Rapakivi-type granite) (Granite, chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende) — igneous

Orbicular granite (likely Rapakivi-type granite)

Granite, chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende

Fossiliferous limestone (likely ammonite/gastropod-bearing) (Bioclastic limestone; predominantly calcite (CaCO₃)) — sedimentary

Fossiliferous limestone (likely ammonite/gastropod-bearing)

Bioclastic limestone; predominantly calcite (CaCO₃)

N/A - Image does not contain a rock or mineral (Anthropogenic textile material) — Non-geological

N/A - Image does not contain a rock or mineral

Anthropogenic textile material

Smurf Rock (Fictional Interpretation) (Cyanus Anthropomorphicus (Geologic Simulation)) — Artificial/Fantasy Object

Smurf Rock (Fictional Interpretation)

Cyanus Anthropomorphicus (Geologic Simulation)

Artificial/Fantasy Object

Conglomerate (Conglomerate) — Sedimentary Rock

Conglomerate

Conglomerate

Sedimentary Rock

Quartz-rich rock, possibly milky quartz (Quartz (SiO₂); exact specimen identification is uncertain from the photograph) — mineral

Quartz-rich rock, possibly milky quartz

Quartz (SiO₂); exact specimen identification is uncertain from the photograph

Likely tumbled iron-stained quartz or chalcedony (Quartz/chalcedony (SiO₂), possibly limonite-coated) — mineral

Likely tumbled iron-stained quartz or chalcedony

Quartz/chalcedony (SiO₂), possibly limonite-coated

Amber (Succinite (C10H16O)) — Organic Mineraloid

Amber

Succinite (C10H16O)

Organic Mineraloid

Amber (Succinite (Formula: C10H16O)) — Organic Mineraloid

Amber

Succinite (Formula: C10H16O)

Organic Mineraloid

Amber (Butterscotch/Egg Yolk Variety) (Succinite (Approx. C10H16O)) — Organic Gemstone

Amber (Butterscotch/Egg Yolk Variety)

Succinite (Approx. C10H16O)

Organic Gemstone

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

Chert (Flint)

Silicon Dioxide (SiO2)

Engineered Quartz Stone (Agglomerated Quartz (SiO2 + Polymer Resin)) — mineral-based composite

Engineered Quartz Stone

Agglomerated Quartz (SiO2 + Polymer Resin)

mineral-based composite

Petrified Wood (Silicified Wood (primarily Silicon Dioxide, SiO2)) — mineral

Petrified Wood

Silicified Wood (primarily Silicon Dioxide, SiO2)

Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Chert

Microcrystalline Quartz (SiO2)

Chert (Jasper variation) (Chert (Microcrystalline Silicon Dioxide, SiO2)) — sedimentary

Chert (Jasper variation)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)