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

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)

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)

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), primarily SiO2 (Silicon Dioxide)) — igneous

Obsidian

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

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)

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

Limonite (Iron Ore)

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

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

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (mostly SiO2)

Obsidian (Obsidian) — igneous

Obsidian

Obsidian

Polished black obsidian (Volcanic glass; primarily silica-rich rhyolitic glass (approximately 70–80% SiO₂)) — igneous

Polished black obsidian

Volcanic glass; primarily silica-rich rhyolitic glass (approximately 70–80% SiO₂)

Polished black obsidian (Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–80% SiO₂)) — igneous

Polished black obsidian

Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–80% SiO₂)

Black obsidian (Volcanic glass; predominantly rhyolitic silica-rich melt (approximately 70–80% SiO₂), lacking crystalline structure) — igneous

Black obsidian

Volcanic glass; predominantly rhyolitic silica-rich melt (approximately 70–80% SiO₂), lacking crystalline structure

Obsidian (likely snowflake-free black variety) (Volcanic glass; primarily SiO₂-rich rhyolitic composition) — igneous

Obsidian (likely snowflake-free black variety)

Volcanic glass; primarily SiO₂-rich rhyolitic composition

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)

Polished mahogany obsidian (Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–75% SiO₂)) — igneous

Polished mahogany obsidian

Volcanic glass; primarily silica-rich rhyolitic composition (approximately 70–75% SiO₂)

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)

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)

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

Mahogany Obsidian

Volcanic glass (Silicon Dioxide with Hematite/Magnetite inclusions)

Obsidian (likely black volcanic glass) (Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition) — igneous

Obsidian (likely black volcanic glass)

Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

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

Snowflake Obsidian

Spherulitic Volcanic Glass (SiO2 + impurities)

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

Obsidian

Volcanic Glass (Silica / SiO2)

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

Limonite Concretion

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

Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

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

Green Opal (Prase Opal)

SiO2 · nH2O (Hydrated Silicon Dioxide)