Rock Identifier

Category

Mineralogical

Browse mineralogical specimens identified by the Rock Identifier community.

Learn about Mineralogical in the encyclopedia

White Beryl

Shungite

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

Green Opal (Prase Opal)

SiO2 · nH2O (Hydrated Silicon Dioxide)

Amber (Fossilized Tree Resin (Succinite)) — mineraloid

Amber

Fossilized Tree Resin (Succinite)

Precious Opal (Hydrated Silicon Dioxide (SiO2·nH2O)) — gemstone

Precious Opal

Hydrated Silicon Dioxide (SiO2·nH2O)

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)

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))

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

White Opal

Hydrated Silica (SiO2·nH2O)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

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)

Tektite (likely Australite) (Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)) — Mineral (specifically a mineraloid)

Tektite (likely Australite)

Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)

Mineral (specifically a mineraloid)

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)

Red Sandstone (Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)) — sedimentary

Red Sandstone

Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)

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)

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

Opal

Hydrated Amorphous Silica (SiO2·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)

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

Opal

Hydrated Silica (SiO2·nH2O)