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

Oil Shale

Peat

Pearl

Lizard Skin Jasper

Opalized Wood

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))

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

Pearl (Biogenic Mineraloid)

Calcium carbonate (CaCO3) primarily as Aragonite

Precious Coral (Corallium rubrum (Calcium carbonate with trace carotene)) — Organic gemstone / Sedimentary mineraloid

Precious Coral

Corallium rubrum (Calcium carbonate with trace carotene)

Organic gemstone / Sedimentary mineraloid

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

Fire Opal (in Matrix)

Hydrated Silica (SiO2·nH2O)

Polished mahogany obsidian (likely) (Volcanic glass; primarily silica-rich rhyolitic glass (SiO₂), with iron oxides) — igneous

Polished mahogany obsidian (likely)

Volcanic glass; primarily silica-rich rhyolitic glass (SiO₂), with iron oxides

Polished black obsidian pyramid/block (Obsidian — natural volcanic glass, chiefly rhyolitic silica (approximately 70–75% SiO₂)) — igneous

Polished black obsidian pyramid/block

Obsidian — natural volcanic glass, chiefly rhyolitic silica (approximately 70–75% SiO₂)

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

Mahogany Obsidian

Volcanic glass (SiO2 with Hematite/Magnetite inclusions)

Mahogany Obsidian (Obsidian (Volcanic Glass with Hematite inclusions)) — igneous

Mahogany Obsidian

Obsidian (Volcanic Glass with Hematite inclusions)

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

Gold Sheen Obsidian

Volcanic Glass (SiO2 + impurities)

Snowflake Obsidian (Volcanic Glass with Spherulite Inclusions (primarily SiO2)) — igneous

Snowflake Obsidian

Volcanic Glass with Spherulite Inclusions (primarily SiO2)

Black Obsidian (Obsidian (Volcanic Glass)) — igneous

Black 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)

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

Obsidian

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

Limonitic Iron Ore / Goethite (Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)) — sedimentary

Limonitic Iron Ore / Goethite

Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)

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

Obsidian

Obsidian (Volcanic Glass, SiO2)

Limonite (Iron Ore) (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Mahogany Obsidian (Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)) — igneous

Mahogany Obsidian

Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)

Mahogany Obsidian (Volcanic glass (SiO2 with Hematite or Magnetite inclusions)) — igneous

Mahogany Obsidian

Volcanic glass (SiO2 with Hematite or Magnetite inclusions)

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

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

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

Limonite (Iron Ore)

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

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

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions

Black Obsidian (Obsidian (Volcanic Glass, ~70% SiO2)) — igneous

Black Obsidian

Obsidian (Volcanic Glass, ~70% SiO2)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

Snowflake Obsidian (Flower Jasper variant) (Vitreous volcanic silicate with cristobalite inclusions) — igneous

Snowflake Obsidian (Flower Jasper variant)

Vitreous volcanic silicate with cristobalite inclusions

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

Mahogany Obsidian

Volcanic Glass (Silicate: SiO2 + Fe2O3)

Obsidian (Volcanic Glass (SiO2 rich)) — Igneous

Obsidian

Volcanic Glass (SiO2 rich)

Limonite (with Pyrite) (Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O) — mineral

Limonite (with Pyrite)

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

Limonite (Ironstone Concretion) (Limonite (Hydrated iron(III) oxide-hydroxide, mixtures of FeO(OH)·nH2O)) — sedimentary

Limonite (Ironstone Concretion)

Limonite (Hydrated iron(III) oxide-hydroxide, mixtures of FeO(OH)·nH2O)

Obsidian (Obsidian) — igneous

Obsidian

Obsidian

Bumblebee Jasper (Calcite with Arsenic and Sulfur inclusions) — sedimentary

Bumblebee Jasper

Calcite with Arsenic and Sulfur inclusions

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

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

Obsidian (Gold Sheen)

Obsidian (SiO2 + impurities)

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

Mahogany Obsidian

Volcanic Glass (SiO2 + Fe2O3)

Mahogany Obsidian (Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)

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

Obsidian

Volcanic Glass (SiO2 + impurities)

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

Snowflake Obsidian

Volcanic Glass (SiO2) with Cristobalite inclusions

Obsidian (Volcanic Glass (Silica / SiO2)) — igneous

Obsidian

Volcanic Glass (Silica / SiO2)

Mahogany Obsidian (Volcanic glass (Silicon Dioxide with Hematite/Magnetite inclusions)) — igneous

Mahogany Obsidian

Volcanic glass (Silicon Dioxide with Hematite/Magnetite inclusions)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

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

Snowflake Obsidian

Spherulitic Volcanic Glass (SiO2 + impurities)