Rock Identifier

Category

Igneous Rock (Volcanic Glass)

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

Banded Agate (specifically Botswana Agate appearance) (Silicon Dioxide (SiO2)) — mineral

Banded Agate (specifically Botswana Agate appearance)

Silicon Dioxide (SiO2)

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

Yellow Agate / Chalcedony

Silicon Dioxide (SiO2)

mineral
Yellow Agate (Agate (Varietal form of Chalcedony/Quartz, SiO2)) — mineral

Yellow Agate

Agate (Varietal form of Chalcedony/Quartz, SiO2)

mineral
Peridot (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

mineral
Chalcedony (Moonstone variant or White Agate) (Silicon Dioxide (SiO₂)) — mineral

Chalcedony (Moonstone variant or White Agate)

Silicon Dioxide (SiO₂)

mineral
Carnelian (Carnelian (SiO2)) — mineral

Carnelian

Carnelian (SiO2)

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

Milky 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

Milky Quartz

Quartz / Silicon Dioxide (SiO2)

mineral
Breccia (Breccia - Clastic sedimentary rock) — sedimentary

Breccia

Breccia - Clastic sedimentary rock

sedimentary
Amethyst Geodes (Silicon Dioxide (Quartz with Iron impurities), SiO2) — mineral

Amethyst Geodes

Silicon Dioxide (Quartz with Iron impurities), SiO2

mineral
Granite (Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)

igneous
Granite featuring Quartz Vein (Granite with hydrothermal silica (SiO2) intrusion) — igneous

Granite featuring Quartz Vein

Granite with hydrothermal silica (SiO2) intrusion

igneous
Granodiorite (Granodiorite (NaAlSi3O8 to CaAl2Si2O8 / SiO2)) — Igneous

Granodiorite

Granodiorite (NaAlSi3O8 to CaAl2Si2O8 / SiO2)

Igneous
Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

metamorphic
Sandstone (likely Quartz Sandstone) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (likely Quartz Sandstone)

Arenite (composed primarily of SiO2)

sedimentary
Feldspathic Granite (likely Syenite or Granite Pegmatite) (Phaneritic Acidic Igneous Rock (KAlSi3O8 dominant with SiO2)) — igneous

Feldspathic Granite (likely Syenite or Granite Pegmatite)

Phaneritic Acidic Igneous Rock (KAlSi3O8 dominant with SiO2)

igneous
Porphyritic Rhyolite (Porphyritic Rhyolite (compositionally similar to granite)) — igneous

Porphyritic Rhyolite

Porphyritic Rhyolite (compositionally similar to granite)

igneous
Druzy Quartz (Crystalline Silicon Dioxide (SiO2)) — mineral

Druzy Quartz

Crystalline Silicon Dioxide (SiO2)

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

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

mineral
Sandstone (Arenite (SiO2 predominantly)) — sedimentary

Sandstone

Arenite (SiO2 predominantly)

sedimentary
Turquoise (Hydrous phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Hydrous phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

mineral
Tektite (Indochinite) (Tektite (High-silica natural glass)) — mineraloid / impact glass

Tektite (Indochinite)

Tektite (High-silica natural glass)

mineraloid / impact glass
Common Opal with Host Rock (Opal (Hydrated silica, SiO2·nH2O)) — mineral

Common Opal with Host Rock

Opal (Hydrated silica, SiO2·nH2O)

mineral
Peridot (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

mineral
Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

metamorphic
Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

sedimentary
Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz

Quartz (SiO2 - Silicon Dioxide)

Mineral
Dyed Agate (Chalcedony (Silicon Dioxide, SiO2)) — mineral

Dyed Agate

Chalcedony (Silicon Dioxide, SiO2)

mineral
Jasper (Jasper (Silicate - SiO2)) — sedimentary

Jasper

Jasper (Silicate - SiO2)

sedimentary
Banded Gneiss (Gneiss (pronounced "nice")) — metamorphic

Banded Gneiss

Gneiss (pronounced "nice")

metamorphic
Citrine Quartz (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

mineral
Gneiss (Gneiss) — metamorphic

Gneiss

Gneiss

metamorphic
Epidote in Matrix (Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)) — metamorphic

Epidote in Matrix

Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic
Quartzite Pebbler (Quartzite (SiO2)) — metamorphic

Quartzite Pebbler

Quartzite (SiO2)

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

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

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

Olivine

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

mineral
Quartz Vein in Sedimentary Rock (Silicon Dioxide (SiO2) with host Chert or Limestone) — mineral

Quartz Vein in Sedimentary Rock

Silicon Dioxide (SiO2) with host Chert or Limestone

mineral
Chert / Flint (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert / Flint

Chert (Cryptocrystalline Silica, SiO2)

sedimentary
Chert (Jasper) (Microcrystalline Quartz (SiO2) with iron oxide impurities) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2) with iron oxide impurities

sedimentary
Chert Breccia (Brecciated Microcrystalline Quartz (SiO2)) — sedimentary

Chert Breccia

Brecciated Microcrystalline Quartz (SiO2)

sedimentary
Chert (Field Stone/Pebble) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone/Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

sedimentary