Rock Identifier

Category

Organic (Non Geological)

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

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

Chert (Flint variety)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Chert (Commonly known as Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Commonly known as Flint)

Microcrystalline Quartz (SiO2)

Tumbled brown jasper (Microcrystalline quartz/chalcedony (SiO₂), commonly iron-oxide stained) — sedimentary

Tumbled brown jasper

Microcrystalline quartz/chalcedony (SiO₂), commonly iron-oxide stained

Fossilized Shark Tooth (Chondrichthyes (Class)) — fossil

Fossilized Shark Tooth

Chondrichthyes (Class)

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

Chert (Black Flint)

Silicon Dioxide (SiO2)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Chert (specifically Flint) (Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (specifically Flint)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

Chert (and Limestone) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Limestone)

Silicon Dioxide (SiO2)

Chert (and Flint) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (and Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Nodule)

Chert (Microcrystalline Quartz, SiO2)

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

Chert (Flint)

Cryptocrystalline quartz (SiO2)

Coal (Bituminous Coal / Anthracite) — sedimentary

Coal

Bituminous Coal / Anthracite

Granite (Granite (quartz–feldspar intrusive igneous rock)) — igneous

Granite

Granite (quartz–feldspar intrusive igneous rock)

Blue-dyed tumbled quartz or glass imitation (Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image) — mineral

Blue-dyed tumbled quartz or glass imitation

Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image

Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 + impurities)

Limestone (with weathering rind) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (with weathering rind)

Calcium Carbonate (CaCO3)

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

Chert (Jasper variation)

Microcrystalline Quartz (SiO2)

Chert (specifically Flint Arrowhead) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (specifically Flint Arrowhead)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Obsidian (Black Obsidian) (Amorphous volcanic glass (primarily SiO2)) — igneous

Obsidian (Black Obsidian)

Amorphous volcanic glass (primarily SiO2)

Likely blue glass or synthetic gemstone jewelry (Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass) — gemstone

Likely blue glass or synthetic gemstone jewelry

Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Black Obsidian (Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)) — igneous

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Concrete or asphalt-like aggregate surface with a dark fragment (Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock) — sedimentary

Concrete or asphalt-like aggregate surface with a dark fragment

Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Quartzite (Metamorphic Quartzite) — metamorphic

Quartzite

Metamorphic Quartzite

Pink shell fragment (Calcium carbonate, likely aragonite or calcite (CaCO₃); probably a bivalve or gastropod shell fragment) — fossil

Pink shell fragment

Calcium carbonate, likely aragonite or calcite (CaCO₃); probably a bivalve or gastropod shell fragment

Grey Quartzite Pebble (Quartzite (primarily SiO2 - Silicon Dioxide)) — metamorphic

Grey Quartzite Pebble

Quartzite (primarily SiO2 - Silicon Dioxide)

Black Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Black Obsidian

Volcanic Glass (predominantly SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

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

Chert (Pink Jasper)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Mudstone variety with Oxidation) (Silicon dioxide (SiO2)) — sedimentary

Chert (Jasper/Mudstone variety with Oxidation)

Silicon dioxide (SiO2)

Tumbled green aventurine (likely) (Quartz (SiO₂) with fuchsite or other green mica inclusions) — mineral

Tumbled green aventurine (likely)

Quartz (SiO₂) with fuchsite or other green mica inclusions

Dalmatian jasper (Orbicular microcrystalline quartz rock, commonly rhyolitic or volcanic-feldspar matrix with black arfvedsonite/alkali-amphibole inclusions) — igneous

Dalmatian jasper

Orbicular microcrystalline quartz rock, commonly rhyolitic or volcanic-feldspar matrix with black arfvedsonite/alkali-amphibole inclusions

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Slag Glass (Anthropogenic Amorphous Silicon Dioxide) — mineral

Slag Glass

Anthropogenic Amorphous Silicon Dioxide

Glauconite sand (Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2) — sedimentary

Glauconite sand

Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)

Small rounded brown stone, likely weathered iron-rich rock (Indeterminate; possibly ferruginous sandstone, ironstone, or weathered basalt) — sedimentary

Small rounded brown stone, likely weathered iron-rich rock

Indeterminate; possibly ferruginous sandstone, ironstone, or weathered basalt