Rock Identifier

Category

Igneous Rock (Volcanic Glass)

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

Amethyst (Tumbled) (Quartz (Silicon Dioxide, SiO2) with iron impurities) — mineral

Amethyst (Tumbled)

Quartz (Silicon Dioxide, SiO2) with iron impurities

Quartz (Milky/Common Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common Quartz)

Silicon Dioxide (SiO2)

Granite (Phaneritic Felsic Igneous Rock (Main minerals: SiO2, KAlSi3O8, NaAlSi3O8)) — igneous

Granite

Phaneritic Felsic Igneous Rock (Main minerals: SiO2, KAlSi3O8, NaAlSi3O8)

Quartz (Quartz (SiO₂)) — mineral

Quartz

Quartz (SiO₂)

Sandstone (likely Quartzose) (Sandstone (Principally SiO2)) — sedimentary

Sandstone (likely Quartzose)

Sandstone (Principally SiO2)

Quartz (Milky/Common) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous) (Arenite (Fe2O3 stained)) — sedimentary

Sandstone (Ferruginous)

Arenite (Fe2O3 stained)

Sandstone (likely Arkosic or Lithic Sandstone) (Arenite (SiO2 based with mineral inclusions)) — sedimentary

Sandstone (likely Arkosic or Lithic Sandstone)

Arenite (SiO2 based with mineral inclusions)

Sandstone (Quartzose) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Quartzose)

Arenite (primarily SiO2)

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

Mica (Muscovite)

Muscovite (KAl2(AlSi3O10)(OH)2)

Glass Nugget (Tumbled Glass) (Amorphous Silicon Dioxide (SiO2) with additives) — mineraloid (man-made)

Glass Nugget (Tumbled Glass)

Amorphous Silicon Dioxide (SiO2) with additives

mineraloid (man-made)

Aventurine (Aventurine Quartz (SiO2 with inclusions)) — Mineral

Aventurine

Aventurine Quartz (SiO2 with inclusions)

Moss Agate (Chalcedony (Silicon Dioxide / SiO2)) — mineral

Moss Agate

Chalcedony (Silicon Dioxide / SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Basalt River Stone (Basalt) — igneous

Basalt River Stone

Basalt

Obsidian and Phantom Quartz (Volcanic Glass (SiO2 + MgO + Fe3O4) and Crystalline Quartz (SiO2)) — igneous and mineral

Obsidian and Phantom Quartz

Volcanic Glass (SiO2 + MgO + Fe3O4) and Crystalline Quartz (SiO2)

igneous and mineral

Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

Pink Granite (Phaneritic Felsic Igneous Rock (Granite)) — igneous

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Granodiorite (foreground) and Rose Quartz (background) (Granodiorite / Quartz (SiO2)) — igneous

Granodiorite (foreground) and Rose Quartz (background)

Granodiorite / Quartz (SiO2)

Granodiorite (Granodiorite (Intermediate intrusive igneous rock)) — igneous

Granodiorite

Granodiorite (Intermediate intrusive igneous rock)

Basalt (Basalt (Aphanitic Mafic Igneous Rock)) — igneous

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Chalcedony (Banded/Mottled Variety) (Chalcedony (a cryptocrystalline variety of Quartz, SiO2)) — Mineral

Chalcedony (Banded/Mottled Variety)

Chalcedony (a cryptocrystalline variety of Quartz, SiO2)

Agate Geode (Microcrystalline Quartz (SiO2)) — mineral

Agate Geode

Microcrystalline Quartz (SiO2)

Pink Dyed Agate (Silicon Dioxide (SiO2) - Variety Agate) — mineral

Pink Dyed Agate

Silicon Dioxide (SiO2) - Variety Agate

Agate (Silicon dioxide (SiO2)) — mineral

Agate

Silicon dioxide (SiO2)

Agate (Silicon Dioxide (SiO2) - variety: Chalcedony) — mineral

Agate

Silicon Dioxide (SiO2) - variety: Chalcedony

Blue Dyed Agate (Silicon Dioxide (SiO2) with artificial pigment) — mineral

Blue Dyed Agate

Silicon Dioxide (SiO2) with artificial pigment

Jasper with Agate Inclusions (Jasper (Silicon Dioxide, SiO2) with Chalcedony/Agate) — sedimentary

Jasper with Agate Inclusions

Jasper (Silicon Dioxide, SiO2) with Chalcedony/Agate

Dyed Agate (Silicon Dioxide (SiO2) - variety Chalcedony) — mineral

Dyed Agate

Silicon Dioxide (SiO2) - variety Chalcedony

Aragonite / Calcite Geode (Calcium Carbonate (CaCO3)) — mineral

Aragonite / Calcite Geode

Calcium Carbonate (CaCO3)

Howlite and Purple Amethyst Druzy (Calcium Borosilicate Hydroxide (Howlite) and Silicon Dioxide (Quartz/Amethyst)) — mineral

Howlite and Purple Amethyst Druzy

Calcium Borosilicate Hydroxide (Howlite) and Silicon Dioxide (Quartz/Amethyst)

Carnelian (Orange Agate/Chalcedony) (Silicon Dioxide (SiO2) - variety of Chalcedony) — mineral

Carnelian (Orange Agate/Chalcedony)

Silicon Dioxide (SiO2) - variety of Chalcedony

Porphyritic Rhyolite (Rhyolite (Porphyritic)) — igneous

Porphyritic Rhyolite

Rhyolite (Porphyritic)

Quartz Vein in Sedimentary Matrix (Silicon Dioxide (SiO2) with host rock) — mineral

Quartz Vein in Sedimentary Matrix

Silicon Dioxide (SiO2) with host rock

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

Blue Apatite

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

Garnet (Almandine (Fe3Al2(SiO4)3)) — mineral

Garnet

Almandine (Fe3Al2(SiO4)3)

Carnelian Agate (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide impurities

Jasper (with Agate/Chalcedony inclusions) (Silicon Dioxide (SiO2)) — sedimentary

Jasper (with Agate/Chalcedony inclusions)

Silicon Dioxide (SiO2)

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

Mexican Crazy Lace Agate

Silicon Dioxide (SiO2) with iron and aluminum inclusions

Carnelian Agate (Silicon dioxide (SiO2) - Chalcedony variety) — mineral

Carnelian Agate

Silicon dioxide (SiO2) - Chalcedony variety

Granite with Orthoclase and Hematite Staining (Phaneritic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)) — igneous

Granite with Orthoclase and Hematite Staining

Phaneritic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)