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.

Diorite (Phaneritic Intermediate Igneous Rock) — igneous

Diorite

Phaneritic Intermediate Igneous Rock

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

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Ferruginous Sandstone (Gozzan/Ironstone) (Arenite with Limonite/Goethite cement (FeO(OH)·nH2O)) — sedimentary

Ferruginous Sandstone (Gozzan/Ironstone)

Arenite with Limonite/Goethite cement (FeO(OH)·nH2O)

Dendritic Opal (Opalized Chalcedony with Manganese Inclusions (SiO2 · nH2O)) — mineral

Dendritic Opal

Opalized Chalcedony with Manganese Inclusions (SiO2 · nH2O)

Specular Hematite (Specularite) (Iron Oxide (Fe2O3)) — mineral

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Quartz (Iron-Stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Dendritic Agate (Tree Agate) (Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions) — mineral

Dendritic Agate (Tree Agate)

Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions

Quartz with Iron Staining (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Quartz with Iron Staining

Silicon Dioxide (SiO2) with iron oxide impurities

Flower Agate (Chalcedony with Opaque Spherulitic Inclusions (SiO2)) — Mineral

Flower Agate

Chalcedony with Opaque Spherulitic Inclusions (SiO2)

Blue Apatite (Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

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

Obsidian

Volcanic Glass (SiO2 + impurities)

Chrysoprase (Silicon dioxide with nickel impurities (SiO2 + Ni)) — mineral

Chrysoprase

Silicon dioxide with nickel impurities (SiO2 + Ni)

Rhodonite (Manganese Silicate (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Horse Chestnut (Buckeye seed) (Aesculus hippocastanum seed) — Organic (Non-geological)

Horse Chestnut (Buckeye seed)

Aesculus hippocastanum seed

Organic (Non-geological)

Green Aventurine (Silicon dioxide (SiO2) with inclusions of Fuchsite mica) — metamorphic

Green Aventurine

Silicon dioxide (SiO2) with inclusions of Fuchsite mica

Sodalite (Sodalite (Na8(Al6Si6O24)Cl2)) — mineral

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Quartz Pebble (Sea Glass-like Quartz) (Quartz (Silicon Dioxide - SiO2)) — mineral

Quartz Pebble (Sea Glass-like Quartz)

Quartz (Silicon Dioxide - SiO2)

Blue Quartz (specifically Dumortierite Quartz) (Silicon Dioxide (SiO2) with inclusions of Dumortierite (Al7BO3(SiO4)3O3)) — metamorphic

Blue Quartz (specifically Dumortierite Quartz)

Silicon Dioxide (SiO2) with inclusions of Dumortierite (Al7BO3(SiO4)3O3)

Obsidian (Volcanic glass (high silica content based on SiO2)) — igneous

Obsidian

Volcanic glass (high silica content based on SiO2)

Obsidian (Obsidian (Volcanic Glass), primarily SiO2) — igneous

Obsidian

Obsidian (Volcanic Glass), primarily SiO2

Ironstone Concretion / Limonite (Goethite and Limonite (FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion / Limonite

Goethite and Limonite (FeO(OH)·nH2O)

Mahogany Obsidian (Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)

Obsidian (Obsidian (volcanic glass)) — Igneous

Obsidian

Obsidian (volcanic glass)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Ferruginous Quartz (Silicon Dioxide (SiO2) with iron oxide inclusions) — mineral

Ferruginous Quartz

Silicon Dioxide (SiO2) with iron oxide inclusions

Obsidian (Obsidian (principally SiO2/Silicon dioxide)) — igneous

Obsidian

Obsidian (principally SiO2/Silicon dioxide)

Ironstone Concretion (Limonitic/Hematitic Concretion) — sedimentary

Ironstone Concretion

Limonitic/Hematitic Concretion

Sandstone (with manganese staining) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with manganese staining)

Clastic sedimentary rock (primarily SiO2)

Obsidian (Obsidian (volcanic glass, amorphous silica rich rock)) — Igneous

Obsidian

Obsidian (volcanic glass, amorphous silica rich rock)

Amazonite (KAlSi3O8 (Potassium Feldspar, variety of Microcline)) — Mineral

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Ironstone Concretion (Siderite or Hematite-bonded Concretion) — sedimentary

Ironstone Concretion

Siderite or Hematite-bonded Concretion

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

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Scoria (Basaltic Lava Rock) (Vesicular Basalt) — igneous

Scoria (Basaltic Lava Rock)

Vesicular Basalt

Obsidian (Volcanic Glass (SiO2 rich)) — igneous

Obsidian

Volcanic Glass (SiO2 rich)

Sandstone (Banded) (Clastic Sedimentary Rock (primarily Quartz, SiO2)) — sedimentary

Sandstone (Banded)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Blue Apatite (Fluorapatite (Ca5(PO4)3F)) — mineral

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Ironstone Nodule (Ironstone Concretion) (Siderite-rich Mudstone (FeCO3) or Limonite (FeO(OH)·nH2O)) — sedimentary

Ironstone Nodule (Ironstone Concretion)

Siderite-rich Mudstone (FeCO3) or Limonite (FeO(OH)·nH2O)

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

Black Obsidian

Volcanic Glass (Amorphous Silicon Dioxide, SiO2)

Ironstone Concretion / Goethite-Hematite Nodule (Goethite/Hematite (α-FeO(OH) / Fe2O3)) — sedimentary

Ironstone Concretion / Goethite-Hematite Nodule

Goethite/Hematite (α-FeO(OH) / Fe2O3)

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

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)