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

Rock Salt

Asphalt Rock

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Black Obsidian

Obsidian

Pink Obsidian

Sideromelane

Carbonatite

Tachylite

Pumice (Pumice (Volcanic glass with vesicular texture)) — igneous

Pumice

Pumice (Volcanic glass with vesicular texture)

Pumice (Pumice (a highly vesicular volcanic glass)) — igneous

Pumice

Pumice (a highly vesicular volcanic glass)

Weathered quartz-bearing rock, possibly porphyritic rhyolite (Likely altered rhyolite or dacite containing quartz and feldspar; exact identification requires testing) — igneous

Weathered quartz-bearing rock, possibly porphyritic rhyolite

Likely altered rhyolite or dacite containing quartz and feldspar; exact identification requires testing

Basalt Pebble (Extrusive Igneous Rock) — igneous

Basalt Pebble

Extrusive Igneous Rock

Banded metamorphic rock, likely gneiss or metasedimentary slate (Quartz–feldspar–mica gneiss (tentative), possibly containing iron-oxide veins) — metamorphic

Banded metamorphic rock, likely gneiss or metasedimentary slate

Quartz–feldspar–mica gneiss (tentative), possibly containing iron-oxide veins

Snowflake Obsidian (Vitreous Volcanic Rock (Amorphous Silicate), SiO2) — igneous

Snowflake Obsidian

Vitreous Volcanic Rock (Amorphous Silicate), SiO2

Quartz Vein in Host Rock (Silicon Dioxide (SiO2)) — mineral

Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Pumice (Vesicular Rhyolite or Andesite (Amorphous volcanic glass)) — igneous

Pumice

Vesicular Rhyolite or Andesite (Amorphous volcanic glass)

Pumice (Pumice (a highly vesicular amorphous volcanic glass)) — igneous

Pumice

Pumice (a highly vesicular amorphous volcanic glass)

Snowflake Obsidian (Volcanic Glass with Spherulite Inclusions (primarily SiO2)) — igneous

Snowflake Obsidian

Volcanic Glass with Spherulite Inclusions (primarily SiO2)

Olivine in Basalt (Peridot) (Magnesium Iron Silicate (Mg, Fe)2SiO4 in Vesicular Basalt) — igneous

Olivine in Basalt (Peridot)

Magnesium Iron Silicate (Mg, Fe)2SiO4 in Vesicular Basalt

Scoria (volcanic cinder) (Scoria, vesicular basaltic-to-andesitic volcanic rock) — igneous

Scoria (volcanic cinder)

Scoria, vesicular basaltic-to-andesitic volcanic rock

Weathered basalt pebble (Basalt, a mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with olivine and iron-titanium oxides) — igneous

Weathered basalt pebble

Basalt, a mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with olivine and iron-titanium oxides

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

Amethyst (Rough)

Silicon Dioxide with iron impurities (SiO2)

Basalt River Cobble (Basalt (Mafic volcanic rock)) — igneous

Basalt River Cobble

Basalt (Mafic volcanic rock)

Snowflake Obsidian (Volcanic glass containing Cristobalite (SiO2)) — igneous

Snowflake Obsidian

Volcanic glass containing Cristobalite (SiO2)

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

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Obsidian (Obsidian (Volcanic Glass, complex silicate)) — igneous

Obsidian

Obsidian (Volcanic Glass, complex silicate)

Porphyritic Basalt or Porphyritic Andesite (Porphyritic Extrusive Igneous Rock) — igneous

Porphyritic Basalt or Porphyritic Andesite

Porphyritic Extrusive Igneous Rock

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

Amethyst

Amethyst (Silicon Dioxide - SiO2)

Basalt Pebble (Mafic Igneous Rock) — igneous

Basalt Pebble

Mafic Igneous Rock

Porphyry (Porphyritic Basalt / Andesite) (Porphyritic Igneous Rock) — igneous

Porphyry (Porphyritic Basalt / Andesite)

Porphyritic Igneous Rock

Pumice (Pumice (volcanic glass with vesicular texture)) — igneous

Pumice

Pumice (volcanic glass with vesicular texture)

Pumice (Pumice (a highly vesicular volcanic glass)) — igneous

Pumice

Pumice (a highly vesicular volcanic glass)

Obsidian (Obsidian (volcanic glass, amorphous silica rich rock)) — Igneous

Obsidian

Obsidian (volcanic glass, amorphous silica rich rock)

Basalt (Basalt) — Igneous

Basalt

Basalt

Dark gray fine-grained rock fragment (Possibly andesite or basalt; exact identification is not possible from the image alone) — igneous

Dark gray fine-grained rock fragment

Possibly andesite or basalt; exact identification is not possible from the image alone

Vesicular basalt (Basalt, commonly composed of plagioclase, pyroxene, olivine, and volcanic glass) — igneous

Vesicular basalt

Basalt, commonly composed of plagioclase, pyroxene, olivine, and volcanic glass

Basalt (Weathered) (Mafic Igneous Rock) — igneous

Basalt (Weathered)

Mafic Igneous Rock

Dark igneous rock, likely basalt (Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron-titanium oxides) — igneous

Dark igneous rock, likely basalt

Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron-titanium oxides

Agate (Silicon Dioxide (SiO2)) — sedimentary

Agate

Silicon Dioxide (SiO2)

Black volcanic glass (likely obsidian) (Obsidian; predominantly rhyolitic volcanic glass composed chiefly of amorphous SiO₂) — igneous

Black volcanic glass (likely obsidian)

Obsidian; predominantly rhyolitic volcanic glass composed chiefly of amorphous SiO₂

Dark volcanic rock, likely basalt (Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase, pyroxene, and commonly olivine) — igneous

Dark volcanic rock, likely basalt

Basalt; fine-grained mafic volcanic rock composed mainly of plagioclase, pyroxene, and commonly olivine

Mahogany Obsidian (Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)) — igneous

Mahogany Obsidian

Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)

Black Obsidian (Obsidian (Volcanic glass), 70–75% SiO2) — igneous

Black Obsidian

Obsidian (Volcanic glass), 70–75% SiO2

Pumice (Pumice (volcanic glass formed of highly vesicular rough textured rock)) — igneous

Pumice

Pumice (volcanic glass formed of highly vesicular rough textured rock)

Pumice (Pumice (volcanic glass with vesicular texture)) — igneous

Pumice

Pumice (volcanic glass with vesicular texture)

Basalt (Extrusive Igneous Rock) — igneous

Basalt

Extrusive Igneous Rock

Likely pumice or vesicular volcanic rock (Pumice; predominantly volcanic glass (silica-rich, commonly rhyolitic or dacitic)) — igneous

Likely pumice or vesicular volcanic rock

Pumice; predominantly volcanic glass (silica-rich, commonly rhyolitic or dacitic)

Pumice (Felsic Volcanic Glass / Vesicular Rhyolite) — Igneous

Pumice

Felsic Volcanic Glass / Vesicular Rhyolite

Pumice (Vesicular volcanic glass (primarily SiO2)) — igneous

Pumice

Vesicular volcanic glass (primarily SiO2)

Basalt (likely vesicular basalt) (Basalt; predominantly plagioclase, clinopyroxene, and olivine, with possible volcanic glass) — igneous

Basalt (likely vesicular basalt)

Basalt; predominantly plagioclase, clinopyroxene, and olivine, with possible volcanic glass