Rock Identifier

Category

Mineraloid (Anthropogenic)

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

Learn about Mineraloid (Anthropogenic) in the encyclopedia

Shungite

White Beryl

Pearl (Aragonite / Calcium Carbonate (CaCO3)) — mineral

Pearl

Aragonite / Calcium Carbonate (CaCO3)

Fired Clay Brick (Anthropic Rock substitute) (Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)) — metamorphic (man-made / anthropic)

Fired Clay Brick (Anthropic Rock substitute)

Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)

metamorphic (man-made / anthropic)

Obsidian (Volcanic Glass) — igneous

Obsidian

Volcanic Glass

Opal ring (Common opal, likely synthetic or assembled blue-green opal (hydrated amorphous silica, SiO₂·nH₂O)) — gemstone

Opal ring

Common opal, likely synthetic or assembled blue-green opal (hydrated amorphous silica, SiO₂·nH₂O)

Obsidian (likely black obsidian) (Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)) — igneous

Obsidian (likely black obsidian)

Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)

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 (likely black obsidian) (Volcanic glass; primarily SiO₂-rich rhyolitic composition) — igneous

Obsidian (likely black obsidian)

Volcanic glass; primarily SiO₂-rich rhyolitic composition

Amber (Succinite) — mineral

Amber

Succinite

Obsidian (Amorphous volcanic glass (SiO2)) — igneous

Obsidian

Amorphous volcanic glass (SiO2)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Obsidian (Obsidian (Volcanic Glass)) — Igneous

Obsidian

Obsidian (Volcanic Glass)

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

Obsidian (Volcanic Glass (Silica-rich, SiO2)) — igneous

Obsidian

Volcanic Glass (Silica-rich, SiO2)

Obsidian (black volcanic glass) (Obsidian; predominantly silica-rich volcanic glass, commonly rhyolitic (approximately 70–75% SiO₂)) — igneous

Obsidian (black volcanic glass)

Obsidian; predominantly silica-rich volcanic glass, commonly rhyolitic (approximately 70–75% SiO₂)

Pink opal (Common opal, hydrated amorphous silica (SiO₂·nH₂O), commonly colored by trace organic or iron compounds) — mineral

Pink opal

Common opal, hydrated amorphous silica (SiO₂·nH₂O), commonly colored by trace organic or iron compounds

Tumbled black obsidian (likely) (Volcanic glass; primarily rhyolitic silica glass (SiO₂-rich, amorphous)) — igneous

Tumbled black obsidian (likely)

Volcanic glass; primarily rhyolitic silica glass (SiO₂-rich, amorphous)

Obsidian (likely black volcanic glass) (Obsidian; silica-rich, noncrystalline volcanic glass, typically rhyolitic (approximately 70–75% SiO₂)) — igneous

Obsidian (likely black volcanic glass)

Obsidian; silica-rich, noncrystalline volcanic glass, typically rhyolitic (approximately 70–75% SiO₂)

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)

Ferruginous Conglomerate (or Iron-Rich Concrete/Slag) (Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)) — sedimentary

Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)

Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)

Fire Opal (in Matrix) (Hydrated Silica (SiO2·nH2O)) — mineral

Fire Opal (in Matrix)

Hydrated Silica (SiO2·nH2O)

Black obsidian (Volcanic glass; predominantly rhyolitic silica glass (approximately 70–80% SiO₂)) — igneous

Black obsidian

Volcanic glass; predominantly rhyolitic silica glass (approximately 70–80% SiO₂)

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)

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