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)) — mineral

Amber

Succinite (Organic Mineraloid)

Mahogany Obsidian (Volcanic glass (high silica) with inclusions of Magnetite or Hematite) — igneous

Mahogany Obsidian

Volcanic glass (high silica) with inclusions of Magnetite or Hematite

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

Obsidian

Volcanic glass (SiO2 + impurities)

Limonite or Ironstone Nodule (FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)) — sedimentary

Limonite or Ironstone Nodule

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

Black Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Black Obsidian

Volcanic Glass (predominantly SiO2)

Black Obsidian (Volcanic Glass (Amorphous SiO2 with trace impurities)) — igneous

Black Obsidian

Volcanic Glass (Amorphous SiO2 with trace impurities)

Black Obsidian (Volcanic glass) — igneous

Black Obsidian

Volcanic glass

Obsidian (Volcanic Glass) — igneous

Obsidian

Volcanic Glass

Obsidian (Volcanic Glass (Amorphous silicon dioxide with impurities)) — igneous

Obsidian

Volcanic Glass (Amorphous silicon dioxide with impurities)

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

Obsidian

Volcanic Glass (SiO2 + impurities)

Fulgurite (Fulgurite (Lechatelierite)) — metamorphic

Fulgurite

Fulgurite (Lechatelierite)

Black Obsidian (Volcanic Glass (SiO2 + impurities)) — Igneous

Black Obsidian

Volcanic Glass (SiO2 + impurities)

Gold Sheen Obsidian (Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)) — igneous

Gold Sheen Obsidian

Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)

Anthracite Coal (Anthracite (Carbon-rich mineraloid)) — metamorphic

Anthracite Coal

Anthracite (Carbon-rich mineraloid)

Amber (Succinite (Organic Mineraloid) - C10H16O) — mineral

Amber

Succinite (Organic Mineraloid) - C10H16O

Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

Limonite (Ironstone) (Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))) — mineral

Limonite (Ironstone)

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

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

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

White Opal

Hydrated Silica (SiO2·nH2O)

Polished mahogany obsidian (probable) (Volcanic glass; chiefly rhyolitic silica-rich glass (SiO₂), compositionally near rhyolite) — igneous

Polished mahogany obsidian (probable)

Volcanic glass; chiefly rhyolitic silica-rich glass (SiO₂), compositionally near rhyolite

Obsidian (Volcanic Glass (Amorphous Silicon Dioxide)) — igneous

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Obsidian (Volcanic Glass (Amorphous SiO2)) — igneous

Obsidian

Volcanic Glass (Amorphous SiO2)

Obsidian (Volcanic Glass (SiO2 rich)) — igneous

Obsidian

Volcanic Glass (SiO2 rich)

Fulgurite (Fulgurite (Lechatelierite-rich fused silica)) — mineraloid / sedimentary (secondary formation)

Fulgurite

Fulgurite (Lechatelierite-rich fused silica)

mineraloid / sedimentary (secondary formation)

Limonite (Iron Ore) (Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)) — Mineral

Limonite (Iron Ore)

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

Pearl (Organic Mineraloid (CaCO3 + Conchiolin)) — mineral

Pearl

Organic Mineraloid (CaCO3 + Conchiolin)

Abalone Shell (Nacre) (Aragonite (CaCO3) - Biogenic Mineral) — mineral

Abalone Shell (Nacre)

Aragonite (CaCO3) - Biogenic Mineral

Obsidian (Volcanic Glass (70% or more SiO2)) — igneous

Obsidian

Volcanic Glass (70% or more SiO2)

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with impurities)) — Igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Amber in Matrix (Succinite (Carbon-based organic polymer)) — Organic (Sedimentary context)

Amber in Matrix

Succinite (Carbon-based organic polymer)

Organic (Sedimentary context)

Obsidian (Obsidian (Amorphous volcanic glass, predominantly SiO2)) — igneous

Obsidian

Obsidian (Amorphous volcanic glass, predominantly SiO2)

Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with impurities)) — igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

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

Limonite (Iron Ore)

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

Likely obsidian (possibly tektite or slag glass) (Volcanic glass; primarily SiO₂, noncrystalline) — igneous

Likely obsidian (possibly tektite or slag glass)

Volcanic glass; primarily SiO₂, noncrystalline

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

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurity)

Limonite (Iron Ore) (Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Obsidian (Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)) — Igneous

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Jet (Lignite (Anthracite-grade compact coal)) — sedimentary

Jet

Lignite (Anthracite-grade compact coal)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

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

Precious Opal

Hydrated Silica (SiO2·nH2O)

Limonite/Ironstone (Limonite (FeO(OH)·nH2O)) — mineral

Limonite/Ironstone

Limonite (FeO(OH)·nH2O)