Rock Identifier

Category

Igneous Rock (Volcanic Glass)

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

Granite (Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)) — Igneous

Granite

Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)

Igneous
Turquoise (CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O

mineral
Geode (Unopened) (Silica-rich concretion (SiO2)) — sedimentary

Geode (Unopened)

Silica-rich concretion (SiO2)

sedimentary
Greenstone (Greenstone River Pebble) (Greenschist (metamorphosed mafic igneous rock)) — metamorphic

Greenstone (Greenstone River Pebble)

Greenschist (metamorphosed mafic igneous rock)

metamorphic
Quartzite Pebble (Quartzite (SiO2)) — metamorphic

Quartzite Pebble

Quartzite (SiO2)

metamorphic
Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

mineral
Granodiorite (Granodiorite) — igneous

Granodiorite

Granodiorite

igneous
Sunstone (Orthoclase Feldspar variant) (Orthoclase (KAlSi3O8) with inclusions) — mineral

Sunstone (Orthoclase Feldspar variant)

Orthoclase (KAlSi3O8) with inclusions

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

Quartz Geode (Smoky Quartz)

Silicon Dioxide (SiO2)

mineral
Amethyst (SiO2 (Silicon Dioxide)) — Mineral

Amethyst

SiO2 (Silicon Dioxide)

Mineral
Vesicular Basalt with Opal or Quartz (Vesicular Basalt (Amorphous SiO2.nH2O if Opal)) — igneous

Vesicular Basalt with Opal or Quartz

Vesicular Basalt (Amorphous SiO2.nH2O if Opal)

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

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

mineral
Sandstone (Arenite (SiO2 based with quartz grains)) — sedimentary

Sandstone

Arenite (SiO2 based with quartz grains)

sedimentary
Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

sedimentary
Granite (Phaneritic Plutonic Felsic Rock) — igneous

Granite

Phaneritic Plutonic Felsic Rock

igneous
Olivine (Peridot) (Magnesium Iron Silicate (Mg,Fe)2SiO4) — mineral

Olivine (Peridot)

Magnesium Iron Silicate (Mg,Fe)2SiO4

mineral
Chalcedony in Host Rock (Silicon Dioxide (SiO2)) — mineral

Chalcedony in Host Rock

Silicon Dioxide (SiO2)

mineral
Banded Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (Metamorphic Rock)

metamorphic
Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

sedimentary
Sandstone (with Concretion) (Arenite / Quartzose Sandstone) — sedimentary

Sandstone (with Concretion)

Arenite / Quartzose Sandstone

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

Sandstone (Quartzose)

Arenite (primarily SiO2)

sedimentary
Carnelian (Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)

mineral
Prehnite (Prehnite - Ca2Al(AlSi3O10)(OH)2) — mineral

Prehnite

Prehnite - Ca2Al(AlSi3O10)(OH)2

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

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

mineral
Carnelian Agate (Silicon Dioxide (SiO2) with Iron Oxide impurities) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) with Iron Oxide impurities

mineral
Turquoise (Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

Hydrated phosphate of copper and aluminum, CuAl6(PO4)4(OH)8·4H2O

mineral
Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

mineral
Milky Quartz (Quartz (Silicon Dioxide, SiO2)) — mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

mineral
Pink Granite / Gneiss (Felsic Plutonic Rock (Granite) with Gneissic banding) — igneous / metamorphic

Pink Granite / Gneiss

Felsic Plutonic Rock (Granite) with Gneissic banding

igneous / metamorphic
Man-made Jewelry (Metal and Glass/Plastic) (Synthetic Alloy and Amorphous Solid (SiO2/Polymer)) — not a rock

Man-made Jewelry (Metal and Glass/Plastic)

Synthetic Alloy and Amorphous Solid (SiO2/Polymer)

not a rock
Chert / River Pebble (Silicon Dioxide (SiO2)) — sedimentary

Chert / River Pebble

Silicon Dioxide (SiO2)

sedimentary
Olivine (Peridot when gem-quality) (Olivine Group (Magnesium Iron Silicate, (Mg,Fe)2SiO4)) — mineral

Olivine (Peridot when gem-quality)

Olivine Group (Magnesium Iron Silicate, (Mg,Fe)2SiO4)

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

Magnetite / Iron Ore

Magnetite (Fe3O4)

mineral
Granitoid (Granitic Rock) (Granitoid (Quartzo-feldspathic plutonic rock)) — igneous

Granitoid (Granitic Rock)

Granitoid (Quartzo-feldspathic plutonic rock)

igneous
Pink Granite (Potassium-rich Granite) (Phaneritic Felsic Igneous Rock (primarily SiO2, Al2O3, K2O)) — Igneous

Pink Granite (Potassium-rich Granite)

Phaneritic Felsic Igneous Rock (primarily SiO2, Al2O3, K2O)

Igneous
Sunstone (Oligoclase (Plagioclase Feldspar), (Na,Ca)(Si,Al)4O8) — mineral

Sunstone

Oligoclase (Plagioclase Feldspar), (Na,Ca)(Si,Al)4O8

mineral
Biotite Mica (Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)) — mineral

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)

mineral
Blue Sapphire (Corundum (Al2O3)) — mineral

Blue Sapphire

Corundum (Al2O3)

mineral
Muscovite Mica (Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2) — mineral

Muscovite Mica

Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

mineral
Muscovite Mica (on Quartz Matrix) (Muscovite - KAl2(AlSi3O10)(OH)2) — mineral

Muscovite Mica (on Quartz Matrix)

Muscovite - KAl2(AlSi3O10)(OH)2

mineral
Pink Granite (Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)) — igneous

Pink Granite

Phaneritic Felsic Igneous Rock (Rich in K-Feldspar)

igneous