Rock Identifier

Category

Organic (Mineraloid)

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

Learn about Organic (Mineraloid) in the encyclopedia

Shungite

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Petrified Wood

Amber

Jet

Peat

Oil Shale

Pearl

Lizard Skin Jasper

Opalized Wood

Snowflake Obsidian (Volcanic Glass (SiO2) with Cristobalite inclusions) — igneous

Snowflake Obsidian

Volcanic Glass (SiO2) with Cristobalite inclusions

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

Obsidian

Volcanic Glass (SiO2 + impurities)

Mahogany Obsidian (Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)) — igneous

Mahogany Obsidian

Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)

Green Opal (Prase Opal) (SiO2 · nH2O (Hydrated Silicon Dioxide)) — mineral

Green Opal (Prase Opal)

SiO2 · nH2O (Hydrated Silicon Dioxide)

Yellow Ocher (Limonite) (Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O) — mineral

Yellow Ocher (Limonite)

Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O

Limonite (Iron Ore/Sandstone mixture) (Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix) — mineral

Limonite (Iron Ore/Sandstone mixture)

Limonite (FeO(OH)·nH2O) often mixed with Goethite and sedimentary matrix

Obsidian (Volcanic Glass (Amorphous Silica)) — igneous

Obsidian

Volcanic Glass (Amorphous Silica)

Tumbled black stone, likely black obsidian (Obsidian — natural volcanic glass, primarily SiO₂) — igneous

Tumbled black stone, likely black obsidian

Obsidian — natural volcanic glass, primarily SiO₂

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

Obsidian

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

Mahogany Obsidian (Volcanic glass containing Magnetite/Hematite) — igneous

Mahogany Obsidian

Volcanic glass containing Magnetite/Hematite

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

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

Obsidian

Volcanic Glass (predominantly SiO2, approximately 70% or more)

Snowflake Obsidian (Obsidian with Spherulitic Cristobalite (SiO2)) — igneous

Snowflake Obsidian

Obsidian with Spherulitic Cristobalite (SiO2)

Mahogany Obsidian (Obsidian (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Obsidian (SiO2 + Fe2O3)

Limonite (Iron Ore) (Hydrous ferric oxides (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Hydrous ferric oxides (FeO(OH)·nH2O)

Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — Mineral

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Obsidian (Volcanic Glass (Amorphous Silicon Dioxide)) — igneous

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

Obsidian (Volcanic Glass (felsic composition)) — igneous

Obsidian

Volcanic Glass (felsic composition)

Mahogany Obsidian (Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)

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

Obsidian

Volcanic Glass (Silicon Dioxide with impurities)

Obsidian (Obsidian (Amorphous volcanic glass, SiO2 with impurities)) — igneous

Obsidian

Obsidian (Amorphous volcanic glass, SiO2 with impurities)

Snowflake Obsidian (Volcanic glass containing Spherulites (SiO2)) — igneous

Snowflake Obsidian

Volcanic glass containing Spherulites (SiO2)

Opalite (Man-made Glass (Synthetic Opalized Glass)) — gemstone

Opalite

Man-made Glass (Synthetic Opalized Glass)

Limonite (Ironstone) Concretion (FeO(OH)·nH2O (Hydrous ferric oxide)) — sedimentary

Limonite (Ironstone) Concretion

FeO(OH)·nH2O (Hydrous ferric oxide)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Snowflake Obsidian (Volcanic Glass with Spherulite inclusions (Chemical composition: 70–75% SiO2 + MgO, Fe3O4)) — igneous

Snowflake Obsidian

Volcanic Glass with Spherulite inclusions (Chemical composition: 70–75% SiO2 + MgO, Fe3O4)

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

Obsidian (Black Obsidian)

Obsidian (Volcanic Glass)

Obsidian (Volcanic Glass (Amorphous SiO2)) — igneous

Obsidian

Volcanic Glass (Amorphous SiO2)

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Common Opal with Host Rock (Opal (Hydrated silica, SiO2·nH2O)) — mineral

Common Opal with Host Rock

Opal (Hydrated silica, SiO2·nH2O)

Mahogany Obsidian (Obsidian (volcanic glass with hematite/magnetite inclusions)) — igneous

Mahogany Obsidian

Obsidian (volcanic glass with hematite/magnetite inclusions)

Precious Opal (Hydrated Silica (SiO2·nH2O)) — mineral

Precious Opal

Hydrated Silica (SiO2·nH2O)

Precious Opal (Hydrated Silicon Dioxide (SiO2·nH2O)) — gemstone

Precious Opal

Hydrated Silicon Dioxide (SiO2·nH2O)

Baltic Amber (Butterscotch variety) (Succinite) — Organic Gemstone/Mineraloid

Baltic Amber (Butterscotch variety)

Succinite

Organic Gemstone/Mineraloid

Baltic Amber (Butterscotch or Egg Yolk Variety) (Succinite (C10H16O)) — Organic Gemstone (Mineraloid)

Baltic Amber (Butterscotch or Egg Yolk Variety)

Succinite (C10H16O)

Organic Gemstone (Mineraloid)

Black Opal (Triplet) (Hydrated Silica (SiO2·nH2O)) — mineral

Black Opal (Triplet)

Hydrated Silica (SiO2·nH2O)

Obsidian (Volcanic glass (silica-rich rhyolitic melt; primarily SiO₂)) — igneous

Obsidian

Volcanic glass (silica-rich rhyolitic melt; primarily SiO₂)

Obsidian (Obsidian (Extrusive Volcanic Glass)) — igneous

Obsidian

Obsidian (Extrusive Volcanic Glass)

Obsidian (Volcanic Glass (comprised primarily of SiO2)) — Igneous

Obsidian

Volcanic Glass (comprised primarily of SiO2)

Opalite (Synthetic Glass (Hydrated Crystalline Silicon Dioxide simulation)) — mineral

Opalite

Synthetic Glass (Hydrated Crystalline Silicon Dioxide simulation)