Rock Identifier

Category

Mineraloid (Organic)

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

Learn about Mineraloid (Organic) in the encyclopedia

Shungite

Sapropel

Bituminous Shale

Bituminous Shale

Black Shale

Petrified Wood

Amber

Jet

Peat

Oil Shale

Pearl

Lizard Skin Jasper

Opalized Wood

Black Obsidian (Volcanic Glass (SiO2)) — igneous

Black Obsidian

Volcanic Glass (SiO2)

Snowflake Obsidian (Volcanic glass containing Spherulitic Cristobalite (SiO2)) — igneous

Snowflake Obsidian

Volcanic glass containing Spherulitic Cristobalite (SiO2)

Obsidian (Volcanic Glass (70-75% SiO2)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2)

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

Mahogany Obsidian

Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)

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

Opal

Hydrated Silica (SiO2·nH2O)

Gold Sheen Obsidian (Obsidian (volcanic glass with SiO2 + gas inclusions)) — igneous

Gold Sheen Obsidian

Obsidian (volcanic glass with SiO2 + gas inclusions)

Limonite (Iron Ore) (FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)) — mineral

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide mixture)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

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

White Precious Opal

Hydrated Silica (SiO2·nH2O)

Limonite (Hydrated Iron Oxide / Bog Iron) (FeO(OH)·nH2O) — Mineral (Sedimentary context)

Limonite (Hydrated Iron Oxide / Bog Iron)

FeO(OH)·nH2O

Mineral (Sedimentary context)

Opalite (Man-made opalescent glass) — gemstone

Opalite

Man-made opalescent glass

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

Gold Sheen Obsidian

Volcanic Glass (SiO2 + impurities)

Obsidian (Amorphous volcanic glass (SiO2)) — igneous

Obsidian

Amorphous volcanic glass (SiO2)

Obsidian (Obsidian (Volcanic Glass)) — Igneous

Obsidian

Obsidian (Volcanic Glass)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Snowflake Obsidian (Volcanic Glass with Spherulite Inclusions (70-75% SiO2)) — igneous

Snowflake Obsidian

Volcanic Glass with Spherulite Inclusions (70-75% SiO2)

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

Limonite (Iron Ore)

Limonite (Hydrous ferric oxides), generic formula FeO(OH)·nH2O

Black Opal Ring (Carved Opal) (Hydrated Silicon Dioxide (SiO2·nH2O)) — gemstone

Black Opal Ring (Carved Opal)

Hydrated Silicon Dioxide (SiO2·nH2O)

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

Opal (Precious Opal)

Hydrated Silica (SiO2·nH2O)

Pearl (Biogenic Mineraloid) (Calcium carbonate (CaCO3) primarily as Aragonite) — mineral

Pearl (Biogenic Mineraloid)

Calcium carbonate (CaCO3) primarily as Aragonite

Mahogany Obsidian (Volcanic Glass with Hematite inclusions) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite inclusions

Black Obsidian (Volcanic Glass (SiO2 + MgO / Fe3O4)) — igneous

Black Obsidian

Volcanic Glass (SiO2 + MgO / Fe3O4)

Black Obsidian (Volcanic Glass (SiO2)) — igneous

Black Obsidian

Volcanic Glass (SiO2)

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

Snowflake Obsidian

Volcanic glass (SiO2) with Cristobalite (SiO2) inclusions

Snowflake Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with Cristobalite inclusions)) — igneous

Snowflake Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with Cristobalite inclusions)

Mahogany Obsidian (Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2) — igneous

Mahogany Obsidian

Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2

Obsidian (Obsidian (volcanic glass; primarily SiO2)) — igneous

Obsidian

Obsidian (volcanic glass; primarily SiO2)

Limonite (Iron-rich Siltstone / Sandstone base) (Hydrous ferric oxide mixture (FeO(OH)·nH2O)) — sedimentary

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Obsidian (Volcanic glass (high silica volcanic rock)) — igneous

Obsidian

Volcanic glass (high silica volcanic rock)

Obsidian (Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)

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

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

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

Snowflake Obsidian

Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)

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

Obsidian

Obsidian (Volcanic Glass), primarily SiO2

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Limonite (Iron Ore Congcretion) (Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore Congcretion)

Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)

Tumbled mahogany obsidian (Volcanic glass; primarily SiO₂ with iron-oxide-rich brown inclusions) — igneous

Tumbled mahogany obsidian

Volcanic glass; primarily SiO₂ with iron-oxide-rich brown inclusions

Opalite (Synthetic Glass (Silica-based)) — gemstone

Opalite

Synthetic Glass (Silica-based)

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

Black Obsidian

Amorphous volcanic glass (SiO2)

Obsidian (specifically Mahogany Obsidian) (Volcanic glass (high silica content, SiO2)) — igneous

Obsidian (specifically Mahogany Obsidian)

Volcanic glass (high silica content, SiO2)

Obsidian with Mahogany Phasing (Volcanic Glass (SiO2 + Fe2O3)) — igneous

Obsidian with Mahogany Phasing

Volcanic Glass (SiO2 + Fe2O3)

Obsidian (Obsidian (Volcanic Glass; SiO2 content > 70%)) — igneous

Obsidian

Obsidian (Volcanic Glass; SiO2 content > 70%)