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 (a highly vesicular felsic volcanic rock)) — igneous

Pumice

Pumice (a highly vesicular felsic volcanic rock)

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

Agate (Silicon Dioxide (Chalcedony), SiO2) — sedimentary

Agate

Silicon Dioxide (Chalcedony), SiO2

Scoria (Extrusive Basaltic Scoria) — igneous

Scoria

Extrusive Basaltic Scoria

Weathered mafic rock, likely basalt (Basalt; fine-grained plagioclase–pyroxene rock, commonly with olivine and iron oxides) — igneous

Weathered mafic rock, likely basalt

Basalt; fine-grained plagioclase–pyroxene rock, commonly with olivine and iron oxides

Weathered basalt boulder (Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine) — igneous

Weathered basalt boulder

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine

Pumice (Pumice (Highly vesicular felsic extrusive igneous rock; primarily SiO2)) — igneous

Pumice

Pumice (Highly vesicular felsic extrusive igneous rock; primarily SiO2)

Likely pumice (Pumice, vesicular volcanic glass (typically rhyolitic to dacitic composition)) — igneous

Likely pumice

Pumice, vesicular volcanic glass (typically rhyolitic to dacitic composition)

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

Black Obsidian

Obsidian (Volcanic glass), 70–75% SiO2

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Possible obsidian or slag glass (Volcanic glass, primarily SiO₂; alternatively industrial iron-rich glassy slag) — igneous

Possible obsidian or slag glass

Volcanic glass, primarily SiO₂; alternatively industrial iron-rich glassy slag

Basalt (Extrusive igneous rock) — igneous

Basalt

Extrusive igneous rock

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

Rounded basalt cobble (Basalt, aphanitic mafic volcanic rock; commonly plagioclase + clinopyroxene ± olivine and iron-titanium oxides) — igneous

Rounded basalt cobble

Basalt, aphanitic mafic volcanic rock; commonly plagioclase + clinopyroxene ± olivine and iron-titanium oxides

Basalt with Olivine and Scoria (Extrusive Igneous Rock) — igneous

Basalt with Olivine and Scoria

Extrusive Igneous Rock

Pumice (Vesicular volcanic glass (primarily Alumino-silicates)) — igneous

Pumice

Vesicular volcanic glass (primarily Alumino-silicates)

Weathered mafic rock, likely basalt (Basalt; primarily plagioclase feldspar, pyroxene, and minor olivine or iron oxides) — igneous

Weathered mafic rock, likely basalt

Basalt; primarily plagioclase feldspar, pyroxene, and minor olivine or iron oxides

Rounded gray pebble, likely basalt or andesite (Fine-grained mafic to intermediate volcanic rock; commonly basalt (plagioclase ± pyroxene/olivine)) — igneous

Rounded gray pebble, likely basalt or andesite

Fine-grained mafic to intermediate volcanic rock; commonly basalt (plagioclase ± pyroxene/olivine)

Basalt with Quartz Veins (Basalt with Quartz or Calcite Veining) — igneous

Basalt with Quartz Veins

Basalt with Quartz or Calcite Veining

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)

Basalt (Polished River Stone) (Aphanitic Mafic Igneous Rock) — igneous

Basalt (Polished River Stone)

Aphanitic Mafic Igneous Rock

Obsidian (Volcanic Glass (Amorphous Silicon Dioxide, SiO2)) — igneous

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide, SiO2)

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

Obsidian

Obsidian (volcanic glass, amorphous silica rich rock)

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

Snowflake Obsidian

Vitreous Volcanic Rock (Amorphous Silicate), SiO2

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

Obsidian

Obsidian (Volcanic Glass, complex silicate)

Black volcanic glass or basalt pendant (Likely basalt (fine-grained mafic rock), possibly obsidian (volcanic glass)) — igneous

Black volcanic glass or basalt pendant

Likely basalt (fine-grained mafic rock), possibly obsidian (volcanic glass)

Tumbled basalt (probable) (Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, commonly with olivine and iron oxides) — igneous

Tumbled basalt (probable)

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

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 (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)

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

Basalt Pebble

Extrusive Igneous Rock (Mafic)

Rhyolite (Rhyolite (Extrusive Felsic Igneous Rock)) — igneous

Rhyolite

Rhyolite (Extrusive Felsic Igneous Rock)

Basalt (Mafic extrusive igneous rock) — igneous

Basalt

Mafic extrusive igneous rock

Quartz vein in dark host rock (Quartz (SiO₂), likely within basalt, diabase, or another mafic volcanic rock) — igneous

Quartz vein in dark host rock

Quartz (SiO₂), likely within basalt, diabase, or another mafic volcanic rock

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

Pumice

Pumice (volcanic glass with vesicular texture)

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

Porphyritic Basalt or Porphyritic Andesite

Porphyritic Igneous Rock

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)

Pumice (Felsic/intermediate vesicular extrusive rock) — igneous

Pumice

Felsic/intermediate vesicular extrusive rock

Likely vesicular basalt (scoria) (Basaltic scoria; chiefly plagioclase, pyroxene, and olivine with volcanic glass) — igneous

Likely vesicular basalt (scoria)

Basaltic scoria; chiefly plagioclase, pyroxene, and olivine with volcanic glass

Basalt River Stone (Basaltic Igneous Rock) — igneous

Basalt River Stone

Basaltic Igneous Rock