Rock Identifier

Category

Industrial Byproduct (Often Mistaken For Obsidian Or Mineral)

Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.

Ferruginous Sandstone (Ironstone) (Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))) — sedimentary

Ferruginous Sandstone (Ironstone)

Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))

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

Rainbow Obsidian

Volcanic Glass (SiO2 + impurities)

Opalite (Man-made Synthetic Glass (Silicon Dioxide with metal additives)) — mineral

Opalite

Man-made Synthetic Glass (Silicon Dioxide with metal additives)

Queen Conch Shell (Biogenic Calcium Carbonate) (Aliger gigas (synonym Strombus gigas); Composition: Aragonite (CaCO3)) — mineral

Queen Conch Shell (Biogenic Calcium Carbonate)

Aliger gigas (synonym Strombus gigas); Composition: Aragonite (CaCO3)

Obsidian (specifically Silver Sheen Obsidian) (Volcanic Glass (approx. 70–75% SiO2 plus MgO, Fe3O4)) — igneous

Obsidian (specifically Silver Sheen Obsidian)

Volcanic Glass (approx. 70–75% SiO2 plus MgO, Fe3O4)

Snowflake Obsidian (Vitreous Volcanic Glass (Siliceous Obsidian with Cristobalite inclusions)) — igneous

Snowflake Obsidian

Vitreous Volcanic Glass (Siliceous Obsidian with Cristobalite inclusions)

Black Obsidian (Volcanic Glass (Amorphous Silicon Dioxide SiO2)) — Igneous

Black Obsidian

Volcanic Glass (Amorphous Silicon Dioxide SiO2)

Quartzite (Meta-quartzite (SiO2)) — metamorphic

Quartzite

Meta-quartzite (SiO2)

Tektite (Indochinite) (Tektite (High-silica natural glass)) — igneous

Tektite (Indochinite)

Tektite (High-silica natural glass)

Quartzite (Quartzite) — metamorphic

Quartzite

Quartzite

Quartz / Quartzite (Quartzite (primarily Silicon Dioxide, SiO2)) — metamorphic

Quartz / Quartzite

Quartzite (primarily Silicon Dioxide, SiO2)

Green Aventurine (Silicon Dioxide (SiO2) with Fuchsite inclusions) — metamorphic

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Quartzite Pebble (Yellow/Cloudy Quartz) (Silicon Dioxide (SiO2) - Recrystallized Sandstone) — metamorphic

Quartzite Pebble (Yellow/Cloudy Quartz)

Silicon Dioxide (SiO2) - Recrystallized Sandstone

Scoria (Lava Rock) (Scoria) — igneous

Scoria (Lava Rock)

Scoria

Flesh-toned Siltstone (Siltstone (composed of microscopic Quartz and Feldspar grains)) — sedimentary

Flesh-toned Siltstone

Siltstone (composed of microscopic Quartz and Feldspar grains)

Black Sapphire (Basaltic Blue Sapphire) (Corundum (Al2O3)) — mineral

Black Sapphire (Basaltic Blue Sapphire)

Corundum (Al2O3)

Snowflake Obsidian (Vitreous volcanic silicate rock (SiO2) with Spherulite inclusions) — igneous

Snowflake Obsidian

Vitreous volcanic silicate rock (SiO2) with Spherulite inclusions

Sodalite (Sodalite (Na4Al3Si3O12Cl)) — Mineral

Sodalite

Sodalite (Na4Al3Si3O12Cl)

Bicolor Quartz (Milk Quartz with Slag or Dark Inclusions) (Silicon Dioxide (SiO2) with impurities) — mineral

Bicolor Quartz (Milk Quartz with Slag or Dark Inclusions)

Silicon Dioxide (SiO2) with impurities

Fossilized Brachiopod (Brachiopoda (Class Rhynchonellata or Spiriferida)) — sedimentary

Fossilized Brachiopod

Brachiopoda (Class Rhynchonellata or Spiriferida)

Cobaltian Calcite (Cobaltoan Calcite) (Cobaltian Calcite (CaCO3 with Co2+ substitution)) — Mineral

Cobaltian Calcite (Cobaltoan Calcite)

Cobaltian Calcite (CaCO3 with Co2+ substitution)

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

Snowflake Obsidian

Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)

Snowflake Obsidian (Volcanic Glass with Cristobalite inclusions (70–75% SiO2)) — Igneous

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions (70–75% SiO2)

Siltstone (Siltstone (composed of clastic quartz and feldspar)) — sedimentary

Siltstone

Siltstone (composed of clastic quartz and feldspar)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Dalmatian Stone (Dalmatian Jasper (a misnomer) / Perthitic Igneous Rock) — igneous

Dalmatian Stone

Dalmatian Jasper (a misnomer) / Perthitic Igneous Rock

Green Aventurine (Quartz) (Silicon Dioxide (SiO2) with inclusions of Fuchsite) — metamorphic

Green Aventurine (Quartz)

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Green Fuchsite in Quartz (sometimes called Green Aventurine) (Fuchsite (Chrome-rich Muscovite) K(Al,Cr)2(AlSi3O10)(OH)2 in Quartz SiO2) — metamorphic

Green Fuchsite in Quartz (sometimes called Green Aventurine)

Fuchsite (Chrome-rich Muscovite) K(Al,Cr)2(AlSi3O10)(OH)2 in Quartz SiO2

Limonite (Ironstone Concretion) (Limonite (Hydrous ferric oxide mixture, FeO(OH)·nH2O)) — sedimentary

Limonite (Ironstone Concretion)

Limonite (Hydrous ferric oxide mixture, FeO(OH)·nH2O)

Iron-stained Quartz (with Limonite/Hematite) (Silicon Dioxide (SiO2) with Iron Oxide inclusions (FeO(OH) or Fe2O3)) — Mineral

Iron-stained Quartz (with Limonite/Hematite)

Silicon Dioxide (SiO2) with Iron Oxide inclusions (FeO(OH) or Fe2O3)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Crushed Stone (Gravel/Aggregates) (Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)) — sedimentary and igneous (mixed)

Crushed Stone (Gravel/Aggregates)

Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)

sedimentary and igneous (mixed)

Rough Diamond (Diamond (pure Carbon, C)) — mineral

Rough Diamond

Diamond (pure Carbon, C)

Bronzite (MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)) — Mineral

Bronzite

MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)

Apache Tear (Hydrated Obsidian (Volcanic Glass)) — igneous

Apache Tear

Hydrated Obsidian (Volcanic Glass)

Limonite (Iron Ore) (Goethite and related iron hydroxides (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Goethite and related iron hydroxides (FeO(OH)·nH2O)

Gold Flakes in Oil (Novelty Specimen) (Native Gold (Au)) — mineral

Gold Flakes in Oil (Novelty Specimen)

Native Gold (Au)

Garnet (Garnet Group (Silicate Minerals), formula varies e.g., Almandine Fe3Al2(SiO4)3) — mineral

Garnet

Garnet Group (Silicate Minerals), formula varies e.g., Almandine Fe3Al2(SiO4)3

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

Black Obsidian

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

Vesicular Basalt (commonly mistaken for Slag) (Scoriaceous Basalt (composed primarily of Plagioclase Feldspar and Pyroxene)) — igneous

Vesicular Basalt (commonly mistaken for Slag)

Scoriaceous Basalt (composed primarily of Plagioclase Feldspar and Pyroxene)

Magnetite / Hematite mix (Iron Ore) (Fe3O4 (Magnetite) / Fe2O3 (Hematite)) — mineral

Magnetite / Hematite mix (Iron Ore)

Fe3O4 (Magnetite) / Fe2O3 (Hematite)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)