Rock Identifier

Category

Igneous Rock (Volcanic Glass)

Browse igneous rock (volcanic glass) specimens identified by the Rock Identifier community.

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Agate (Silicon Dioxide (SiO2)) — mineral

Agate

Silicon Dioxide (SiO2)

Flower Agate (Chalcedony (cryptocrystalline Quartz) with Spherulite inclusions; SiO2) — mineral

Flower Agate

Chalcedony (cryptocrystalline Quartz) with Spherulite inclusions; SiO2

Crazy Lace Agate (Silicon Dioxide (SiO2) with iron and aluminum inclusions) — sedimentary mineral

Crazy Lace Agate

Silicon Dioxide (SiO2) with iron and aluminum inclusions

sedimentary mineral

Quartz Geode / Druzy Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz Geode / Druzy Quartz

Silicon Dioxide (SiO2)

Amethyst (Silicon Dioxide with iron impurities (SiO2)) — mineral

Amethyst

Silicon Dioxide with iron impurities (SiO2)

Dyed Blue Agate (Silicon Dioxide (SiO2)) — Mineral

Dyed Blue Agate

Silicon Dioxide (SiO2)

Fire Agate (Silicon Dioxide (SiO2) with layered Iron Oxide (Limonite/Goethite)) — mineral

Fire Agate

Silicon Dioxide (SiO2) with layered Iron Oxide (Limonite/Goethite)

Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with inclusions) — mineral

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

River Cobble (Quartzite) (Meta-orthoquartzite) — metamorphic

River Cobble (Quartzite)

Meta-orthoquartzite

Muscovite Mica (Muscovite (KAl2(AlSi3O10)(OH)2)) — Mineral

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Quartz (likely a clear or rock crystal variety) (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz (likely a clear or rock crystal variety)

Quartz (SiO2 - Silicon Dioxide)

Sandstone (Arenite (primarily SiO2 - Silicon Dioxide)) — sedimentary

Sandstone

Arenite (primarily SiO2 - Silicon Dioxide)

Sandstone (likely Arkosic) (Clastic Sedimentary Rock (primarily SiO2 with Feldspar)) — sedimentary

Sandstone (likely Arkosic)

Clastic Sedimentary Rock (primarily SiO2 with Feldspar)

Sapphire (Corundum) (Corundum (Al2O3)) — mineral

Sapphire (Corundum)

Corundum (Al2O3)

Quartzite Pebble (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Muscovite Mica (Muscovite (KAl2(AlSi3O10)(OH)2)) — mineral

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Red Jasper with Quartz and Hematite (Silicon Dioxide (SiO2) with Ferric Iron inclusions) — sedimentary

Red Jasper with Quartz and Hematite

Silicon Dioxide (SiO2) with Ferric Iron inclusions

Magnetite (Iron Ore) (Magnetite (Fe3O4)) — mineral

Magnetite (Iron Ore)

Magnetite (Fe3O4)

Quartzite with Quartz Vein (Quartzite (primarily SiO2)) — metamorphic

Quartzite with Quartz Vein

Quartzite (primarily SiO2)

Granite / Gneiss Complex (Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)) — igneous/metamorphic

Granite / Gneiss Complex

Felsic Plutonic Rock (Granite) or High-grade Metamorphic Rock (Gneiss)

igneous/metamorphic

Banded Jasper (Silicon Dioxide (SiO2)) — Mineral/Sedimentary Rock (as a cryptocrystalline variety of quartz)

Banded Jasper

Silicon Dioxide (SiO2)

Mineral/Sedimentary Rock (as a cryptocrystalline variety of quartz)

Muscovite Mica (likely on Quartz/Feldspar) (Muscovite - KAl2(AlSi3O10)(OH)2) — mineral

Muscovite Mica (likely on Quartz/Feldspar)

Muscovite - KAl2(AlSi3O10)(OH)2

Pink Granite (Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)) — igneous

Pink Granite

Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)

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

Quartz Pebble (Sea Glass-like texture)

Silicon Dioxide (SiO2)

Smoky Quartz (SiO2 (Silicon Dioxide)) — mineral

Smoky Quartz

SiO2 (Silicon Dioxide)

Granite (Phaneritic Acidic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Phaneritic Acidic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)

Orca Agate (Chalcedony (SiO2) with various inclusions) — mineral

Orca Agate

Chalcedony (SiO2) with various inclusions

Bloodstone (Heliotrope) (Silicon Dioxide (SiO2) with inclusions of Chlorite or Actinolite) — sedimentary

Bloodstone (Heliotrope)

Silicon Dioxide (SiO2) with inclusions of Chlorite or Actinolite

Banded Agate (specifically Lace Agate type) (Silicon Dioxide (SiO2)) — mineral

Banded Agate (specifically Lace Agate type)

Silicon Dioxide (SiO2)

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Sandstone (likely Arkosic or Lithic Sandstone) (Clastic Sedimentary Rock (SiO2 with assorted minerals)) — sedimentary

Sandstone (likely Arkosic or Lithic Sandstone)

Clastic Sedimentary Rock (SiO2 with assorted minerals)

Garnet (almandine or pyrope variety) (Silicate mineral Group: (Fe, Mg, Mn, Ca)3(Al, Fe, Cr)2(SiO4)3) — mineral

Garnet (almandine or pyrope variety)

Silicate mineral Group: (Fe, Mg, Mn, Ca)3(Al, Fe, Cr)2(SiO4)3

Greenstone / Glauconitic Siltstone (Metabasalt or Glauconite-rich Sedimentary Rock) — metamorphic or sedimentary

Greenstone / Glauconitic Siltstone

Metabasalt or Glauconite-rich Sedimentary Rock

metamorphic or sedimentary

Quartz Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Coquina Jasper (Fossiliferous Chalcedony (SiO2)) — sedimentary

Coquina Jasper

Fossiliferous Chalcedony (SiO2)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Quartzite Pebble (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Quartz with Limonite Staining (Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)) — Mineral

Quartz with Limonite Staining

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)