Rock Identifier

Category

Igneous Rock (Volcanic Glass)

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

Learn about Igneous Rock (Volcanic Glass) in the encyclopedia

Rock Gypsum

Coral Rock

Asphalt Rock

Rock Salt

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Black Obsidian

Obsidian

Pink Obsidian

Sideromelane

Carbonatite

Tachylite

Geode (Quartz nodule / Chalcedony-lined cavity) — sedimentary

Geode

Quartz nodule / Chalcedony-lined cavity

Diorite (Diorite (Plagioclase-rich phaneritic rock)) — igneous

Diorite

Diorite (Plagioclase-rich phaneritic rock)

Diorite (Intermediate Phaneritic Plutonic Rock - Diorite) — igneous

Diorite

Intermediate Phaneritic Plutonic Rock - Diorite

Green Banded Agate (Agate (Variety of Chalcedony/Quartz), SiO2) — mineral

Green Banded Agate

Agate (Variety of Chalcedony/Quartz), SiO2

Basalt (Basalt (Fine-grained extrusive igneous rock)) — igneous

Basalt

Basalt (Fine-grained extrusive igneous rock)

White Quartz (Silicon Dioxide (SiO2)) — mineral

White Quartz

Silicon Dioxide (SiO2)

Granite Pebble (Granite (composed mainly of Quartz, Feldspar, and Mica)) — igneous

Granite Pebble

Granite (composed mainly of Quartz, Feldspar, and Mica)

Yellow Quartz or Citrine Geode/Cluster (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz or Citrine Geode/Cluster

Silicon Dioxide (SiO2)

Lava Rock (Scoria) (Extrusive basaltic scoria) — igneous

Lava Rock (Scoria)

Extrusive basaltic scoria

Jasper or Chalcedony (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper or Chalcedony

Microcrystalline Quartz (SiO2)

Scoria (Lava Rock) (Scoria (Basaltic Scoria)) — Igneous

Scoria (Lava Rock)

Scoria (Basaltic Scoria)

Quartz Geode (with possible Manganese or Goethite coating) (Silicon Dioxide (SiO2)) — mineral

Quartz Geode (with possible Manganese or Goethite coating)

Silicon Dioxide (SiO2)

Amethyst (Silicon Dioxide (SiO2) with trivalent iron (Fe3+) impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with trivalent iron (Fe3+) impurities

Weathered quartz-rich rock, possibly pegmatite or quartzite (Quartz (SiO₂)-rich aggregate; exact identification is uncertain from the photograph) — igneous

Weathered quartz-rich rock, possibly pegmatite or quartzite

Quartz (SiO₂)-rich aggregate; exact identification is uncertain from the photograph

Lava Rock (Scoria) (Scoria (highly vesicular basaltic rock)) — igneous

Lava Rock (Scoria)

Scoria (highly vesicular basaltic rock)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Black Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Mahogany Obsidian (Volcanic glass containing Magnetite/Hematite) — igneous

Mahogany Obsidian

Volcanic glass containing Magnetite/Hematite

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Tektite (Indochinite) (Tektite (Natural silica glass)) — igneous

Tektite (Indochinite)

Tektite (Natural silica glass)

Weathered granitic rock (Granite or granodiorite; mainly quartz, feldspar, and mica/amphibole) — igneous

Weathered granitic rock

Granite or granodiorite; mainly quartz, feldspar, and mica/amphibole

Greenstone (Metamorphic mafic rock (chlorite-actinolite-epidote schist)) — metamorphic

Greenstone

Metamorphic mafic rock (chlorite-actinolite-epidote schist)

Scoria (Vesicular Basalt / Scoria) — igneous

Scoria

Vesicular Basalt / Scoria

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

Basalt

Basalt (Mafic Extrusive Igneous Rock)

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

Rough Sapphire (Corundum)

Corundum (Al2O3)

Basalt with Quartz Vein (Basalt (extrusive igneous rock with SiO2 vein inclusion)) — igneous

Basalt with Quartz Vein

Basalt (extrusive igneous rock with SiO2 vein inclusion)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Red Scoria (Lava Rock) (Scoria (highly vesicular basaltic/andesitic rock)) — igneous

Red Scoria (Lava Rock)

Scoria (highly vesicular basaltic/andesitic rock)

Granite (Granite (composed of Quartz, Feldspar, and Mica)) — igneous

Granite

Granite (composed of Quartz, Feldspar, and Mica)

Granodiorite (Granodiorite) — igneous

Granodiorite

Granodiorite

Basalt (Basalt (Mainly Plagioclase Feldspar and Pyroxene)) — igneous

Basalt

Basalt (Mainly Plagioclase Feldspar and Pyroxene)

Diorite (or Gabbro/Greenschist pebble) (Diorite (Plagioclase Feldspar with Hornblende/Biotite)) — igneous

Diorite (or Gabbro/Greenschist pebble)

Diorite (Plagioclase Feldspar with Hornblende/Biotite)

Quartz (Raw Crystal) (Silicon Dioxide (SiO2)) — mineral

Quartz (Raw Crystal)

Silicon Dioxide (SiO2)

Industrial Slag (Anthropogenic Vitreous Slag) — igneous

Industrial Slag

Anthropogenic Vitreous Slag

Kimberlite (Kimberlite) — igneous

Kimberlite

Kimberlite

Obsidian (Amorphous volcanic glass (primarily SiO2)) — igneous

Obsidian

Amorphous volcanic glass (primarily SiO2)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Scoria (Scoriaceous Basalt) — igneous

Scoria

Scoriaceous Basalt

Banded Agate (Silicon dioxide (SiO2) - variety of Chalcedony) — sedimentary

Banded Agate

Silicon dioxide (SiO2) - variety of Chalcedony

Picture Jasper (SiO2, Microcrystalline Quartz) — mineral

Picture Jasper

SiO2, Microcrystalline Quartz