Rock Identifier

Category

Organic (Non Geological)

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

Chert with Limestone Cortex (Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3)) — sedimentary

Chert with Limestone Cortex

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Acrylic or Resin (Synthetic Imitation) (Polymethyl Methacrylate (PMMA) or Polyepoxide) — Synthetic/Man-made Polymer

Acrylic or Resin (Synthetic Imitation)

Polymethyl Methacrylate (PMMA) or Polyepoxide

Synthetic/Man-made Polymer

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Obsidian (Obsidian (Volcanic glass), 70-75% SiO2) — igneous

Obsidian

Obsidian (Volcanic glass), 70-75% SiO2

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Mixed gemstone bead bracelet (Likely rose quartz, amethyst, and possibly rhodonite or lepidolite beads) — gemstone

Mixed gemstone bead bracelet

Likely rose quartz, amethyst, and possibly rhodonite or lepidolite beads

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

Petrified Wood (Silicified Fossil)

Silicified Wood (SiO2)

Fossiliferous Limestone (Biogenic Sedimentary Rock (CaCO3)) — sedimentary

Fossiliferous Limestone

Biogenic Sedimentary Rock (CaCO3)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Limestone (with Chert) (Calcium Carbonate (CaCO3) / Microcrystalline Quartz (SiO2)) — sedimentary

Limestone (with Chert)

Calcium Carbonate (CaCO3) / Microcrystalline Quartz (SiO2)

Coral Fossil (Hexagonaria) (Hexagonaria sp. (Silica-replaced)) — fossil

Coral Fossil (Hexagonaria)

Hexagonaria sp. (Silica-replaced)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Moqui Marbles (Iron Oxide Concretion (Hematite/Goethite)) — sedimentary

Moqui Marbles

Iron Oxide Concretion (Hematite/Goethite)

Rounded pebble, likely quartzite (Quartzite (dominantly recrystallized quartz, SiO₂); identification is uncertain from the image alone) — metamorphic

Rounded pebble, likely quartzite

Quartzite (dominantly recrystallized quartz, SiO₂); identification is uncertain from the image alone

Fossilized Coral (Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)) — sedimentary

Fossilized Coral

Cnidaria (Anthozoa), often replaced by Calcium Carbonate (CaCO3) or Silica (SiO2)

Fossiliferous Sandstone Pebble (with Crinoid / Shell Impression) (Sandstone containing fossiliferous inclusions (SiO2 matrix with calcite/silica cast fossil)) — sedimentary

Fossiliferous Sandstone Pebble (with Crinoid / Shell Impression)

Sandstone containing fossiliferous inclusions (SiO2 matrix with calcite/silica cast fossil)

Quartzite (Metamorphic Quartz Rock (SiO2)) — metamorphic

Quartzite

Metamorphic Quartz Rock (SiO2)

Mixed Gemstone and Mineral Collection (Silicon Dioxide (SiO2) based minerals and others) — mineral

Mixed Gemstone and Mineral Collection

Silicon Dioxide (SiO2) based minerals and others

Zebra Rock (Zebra Stone / Ribbon Stone) (Siltstone with Ferruginous Banding (Primarily Quartz, Kaolinite, and Hematite)) — sedimentary

Zebra Rock (Zebra Stone / Ribbon Stone)

Siltstone with Ferruginous Banding (Primarily Quartz, Kaolinite, and Hematite)

Sandstone pebble (Sandstone (arenite / quartzarenite)) — sedimentary

Sandstone pebble

Sandstone (arenite / quartzarenite)

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Green aventurine (tumbled) (Quartz, SiO₂, with fuchsite or other mica inclusions) — mineral

Green aventurine (tumbled)

Quartz, SiO₂, with fuchsite or other mica inclusions

Petrified wood (possible) (Silicified wood; fossilized tree tissue, commonly replaced by microcrystalline quartz (SiO₂)) — fossil

Petrified wood (possible)

Silicified wood; fossilized tree tissue, commonly replaced by microcrystalline quartz (SiO₂)

Amber (Copal) (Succiniferous Resin) — mineraloid

Amber (Copal)

Succiniferous Resin

Ironstone Concretion (Boxwork) (Siderite-Limonite Concretion (FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion (Boxwork)

Siderite-Limonite Concretion (FeO(OH)·nH2O)

Tumbled amber-colored pebble (Likely quartz/chert or iron-stained chalcedony; exact identification requires testing) — mineral

Tumbled amber-colored pebble

Likely quartz/chert or iron-stained chalcedony; exact identification requires testing

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (often called Jasper or Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Jasper or Flint)

Silicon Dioxide (SiO2)

Fossil-bearing sedimentary rock, possibly fossil wood or bone (Indeterminate silicified/carbonate fossil in sandstone or mudstone) — fossil

Fossil-bearing sedimentary rock, possibly fossil wood or bone

Indeterminate silicified/carbonate fossil in sandstone or mudstone

Chert (Jasper-like Silicate) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper-like Silicate)

Microcrystalline quartz (SiO2)

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

Chert (Jasper/Flint variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Jasper (specifically a banded or dark variety) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper (specifically a banded or dark variety)

Silicon Dioxide (SiO2) with impurities

Moss Agate (Silicon Dioxide (SiO2) with Manganese or Iron Oxide inclusions) — mineral

Moss Agate

Silicon Dioxide (SiO2) with Manganese or Iron Oxide inclusions

Chert (often called Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)

Chert (specifically Flint or Gray Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (variations include Flint/Novaculite) (Chert (formula: SiO2)) — sedimentary

Chert (variations include Flint/Novaculite)

Chert (formula: SiO2)

Chert (often called Flint or River Rock) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or River Rock)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert / Flint (Chert (SiO2)) — sedimentary

Chert / Flint

Chert (SiO2)

Chert (Jasper/Flint Pebble) (Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint Pebble)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)