Rock Identifier

Category

Mineraloid

Browse mineraloid specimens identified by the Rock Identifier community.

Learn about Mineraloid in the encyclopedia

Shungite

White Beryl

Amber (Succinite (organic mineraloid); Chemical formula: C10H16O) — mineral

Amber

Succinite (organic mineraloid); Chemical formula: C10H16O

Pearl (Biogenic Mineraloid) (Calcium carbonate (Aragonite) and Conchiolin, CaCO3) — mineral

Pearl (Biogenic Mineraloid)

Calcium carbonate (Aragonite) and Conchiolin, CaCO3

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)

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

Pearl (Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3) — mineral

Pearl

Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3

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

Pearl

Aragonite / Calcium Carbonate (CaCO3)

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)

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)

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%)

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

Mahogany Obsidian

Volcanic Glass (SiO2 + Fe2O3)

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

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

Limonite (Iron Stone/Goethite) (Limonite (mixture of hydrated iron oxides, primarily Goethite: α-FeO(OH))) — mineral

Limonite (Iron Stone/Goethite)

Limonite (mixture of hydrated iron oxides, primarily Goethite: α-FeO(OH))

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

Fire Opal (in Matrix)

Hydrated Silica (SiO2·nH2O)

Likely obsidian fragment (Volcanic glass, predominantly silica-rich rhyolitic composition (SiO₂-rich)) — igneous

Likely obsidian fragment

Volcanic glass, predominantly silica-rich rhyolitic composition (SiO₂-rich)

Obsidian (likely Apache tear or flaked obsidian) (Volcanic glass; primarily rhyolitic silica glass (SiO₂-rich, non-crystalline)) — igneous

Obsidian (likely Apache tear or flaked obsidian)

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