Rock Identifier

Category

Mineraloid

Browse mineraloid specimens identified by the Rock Identifier community.

Amber (Succinite (Organic Mineraloid)) — mineral

Amber

Succinite (Organic Mineraloid)

mineral
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

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

Obsidian

Volcanic glass (SiO2 + impurities)

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

Black Obsidian

Volcanic Glass (predominantly SiO2)

igneous
Fulgurite (Fulgurite (Lechatelierite)) — metamorphic

Fulgurite

Fulgurite (Lechatelierite)

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

Black Obsidian

Volcanic Glass (SiO2 + impurities)

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

Gold Sheen Obsidian

Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)

igneous
Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

igneous
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))

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

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

Abalone Shell (Nacre)

Aragonite (CaCO3) - Biogenic Mineral

mineral
Obsidian (Volcanic Glass (SiO2 rich)) — igneous

Obsidian

Volcanic Glass (SiO2 rich)

igneous
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)

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

Anthracite Coal

Anthracite (Carbon-rich mineraloid)

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

Amber

Succinite (Organic Mineraloid) - C10H16O

mineral
Obsidian (Volcanic glass) — igneous

Obsidian

Volcanic glass

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

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

Obsidian

Obsidian (Amorphous volcanic glass, predominantly SiO2)

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

Amber in Matrix

Succinite (Carbon-based organic polymer)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

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

Limonite (Iron Ore)

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

mineral
Pearl (Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3) — mineral

Pearl

Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3

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

Pearl

Organic Mineraloid (CaCO3 + Conchiolin)

mineral
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)

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

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Igneous
Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

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

Jet

Lignite (Anthracite-grade compact coal)

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

Limonite/Ironstone

Limonite (FeO(OH)·nH2O)

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

Precious Opal

Hydrated Silica (SiO2·nH2O)

mineral
Green Opal (Hydrated Silica (SiO2·nH2O)) — mineraloid

Green Opal

Hydrated Silica (SiO2·nH2O)

mineraloid
Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — Mineral

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

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

Opal

Hydrated Silica (SiO2·nH2O)

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

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

igneous
Black Obsidian (Volcanic Glass (SiO2 + impurities like Fe3O4)) — igneous

Black Obsidian

Volcanic Glass (SiO2 + impurities like Fe3O4)

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

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

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

Snowflake Obsidian

Hydrated Volcanic Glass (primarily SiO2) with Cristobalite inclusions

igneous
Amber (Amber (C10H16O)) — mineral

Amber

Amber (C10H16O)

mineral
Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)

igneous
Opal (Hydrated amorphous silica (SiO2·nH2O)) — mineral

Opal

Hydrated amorphous silica (SiO2·nH2O)

mineral
Amber with Inclusion (Succiniferous fossil resin (C10H16O)) — mineraloid

Amber with Inclusion

Succiniferous fossil resin (C10H16O)

mineraloid
Black Pearl (Tahitian Pearl) (Aragonite / Calcite (CaCO3) with Conchiolin) — mineral

Black Pearl (Tahitian Pearl)

Aragonite / Calcite (CaCO3) with Conchiolin

mineral