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

Green Sheen Obsidian (Volcanic Glass (SiO2 with microscopic inclusions)) — igneous

Green Sheen Obsidian

Volcanic Glass (SiO2 with microscopic inclusions)

Vesicular Basalt with Oxidation (Scoriaceous Olivine Basalt (Mafic volcanic rock)) — igneous

Vesicular Basalt with Oxidation

Scoriaceous Olivine Basalt (Mafic volcanic rock)

Obsidian (likely snowflake or smoky obsidian fragment) (Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)) — igneous

Obsidian (likely snowflake or smoky obsidian fragment)

Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)

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

Peridot (Olivine)

Olivine ((Mg, Fe)2SiO4)

Obsidian (Obsidian (principally SiO2)) — igneous

Obsidian

Obsidian (principally SiO2)

Porphyritic Basalt (with Amygdules) (Amygdaloidal Porphyritic Basalt) — igneous

Porphyritic Basalt (with Amygdules)

Amygdaloidal Porphyritic Basalt

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

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

Quartz (Milky Quartz / Quartz Specimen)

Silicon Dioxide (SiO2)

Weathered granite or granitic rock fragment (Granite; chiefly quartz, feldspar, and mica (composition uncertain from image)) — igneous

Weathered granite or granitic rock fragment

Granite; chiefly quartz, feldspar, and mica (composition uncertain from image)

Black Obsidian (Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)) — igneous

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Tumbled Agate (Dyed Blue) (Silicon Dioxide (Chalcedony variety)) — gemstone

Tumbled Agate (Dyed Blue)

Silicon Dioxide (Chalcedony variety)

Mahogany Obsidian (Volcanic glass (SiO2 with Hematite or Magnetite inclusions)) — igneous

Mahogany Obsidian

Volcanic glass (SiO2 with Hematite or Magnetite inclusions)

Obsidian (Obsidian (Volcanic Glass, SiO2 + impurities)) — igneous

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

Porphyritic Basalt (Porphyritic Basalt (with Plagioclase phenocrysts)) — igneous

Porphyritic Basalt

Porphyritic Basalt (with Plagioclase phenocrysts)

Basalt (Basalt) — igneous

Basalt

Basalt

Scoria (Scoria (a vesicular basalt or andesite)) — igneous

Scoria

Scoria (a vesicular basalt or andesite)

Weathered quartz-rich rock, likely granite or granitic gneiss (Granite–gneiss assemblage; mainly quartz (SiO₂), feldspar, and minor mica/amphibole) — igneous

Weathered quartz-rich rock, likely granite or granitic gneiss

Granite–gneiss assemblage; mainly quartz (SiO₂), feldspar, and minor mica/amphibole

Crushed Granite and Basalt (Phaneritic Igneous Rock / Aphanitic Igneous Rock) — igneous

Crushed Granite and Basalt

Phaneritic Igneous Rock / Aphanitic Igneous Rock

Amethyst geode/druse (Quartz, SiO₂; purple variety amethyst) — mineral

Amethyst geode/druse

Quartz, SiO₂; purple variety amethyst

Jasper (Silicon dioxide (Microcrystalline quartz, SiO2)) — mineral

Jasper

Silicon dioxide (Microcrystalline quartz, SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Carnelian (SiO2 (Silicon Dioxide - Chalcedony variant)) — mineral

Carnelian

SiO2 (Silicon Dioxide - Chalcedony variant)

Chert (Chalcedony/Agate variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Chalcedony/Agate variety)

Silicon Dioxide (SiO2)

Basalt (Basalt) — igneous

Basalt

Basalt

Biotite-bearing granite (Granite, composed mainly of quartz (SiO₂), potassium feldspar, plagioclase, and biotite mica) — igneous

Biotite-bearing granite

Granite, composed mainly of quartz (SiO₂), potassium feldspar, plagioclase, and biotite mica

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

Granite

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

Quartz with Iron Oxide Inclusions (Silicon Dioxide (SiO2)) — mineral

Quartz with Iron Oxide Inclusions

Silicon Dioxide (SiO2)

Quartz on Greenstone (Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit) — metamorphic

Quartz on Greenstone

Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit

Basalt with Magnetite (Crystalline Basalt (Primarily Plagioclase and Pyroxene) with Magnetite (Fe3O4)) — igneous

Basalt with Magnetite

Crystalline Basalt (Primarily Plagioclase and Pyroxene) with Magnetite (Fe3O4)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Yooperlite (Syenite clast containing fluorescent Sodalite) (Sodalite-bearing Syenite) — igneous

Yooperlite (Syenite clast containing fluorescent Sodalite)

Sodalite-bearing Syenite

Jasper (Silicon dioxide (SiO2) with impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with impurities

Snowflake Obsidian (Volcanic Glass with Spherulite Inclusions (70-75% SiO2)) — igneous

Snowflake Obsidian

Volcanic Glass with Spherulite Inclusions (70-75% SiO2)

Obsidian (Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)) — igneous

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Yellow Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Diorite (Salt and Pepper Rock) (Diorite) — igneous

Diorite (Salt and Pepper Rock)

Diorite

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Granite (Granite) — Igneous

Granite

Granite

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

Quartz (Druzy)

Silicon Dioxide (SiO2)

Vesicular Basalt with Zeolite (Mafic volcanic rock with Hydrated Aluminosilicate minerals (Zeolite group)) — igneous

Vesicular Basalt with Zeolite

Mafic volcanic rock with Hydrated Aluminosilicate minerals (Zeolite group)

Basalt with Desert Varnish (Mafic Volcanic Rock (Fe/Mg rich Silicate)) — igneous

Basalt with Desert Varnish

Mafic Volcanic Rock (Fe/Mg rich Silicate)

Jasper (Quartz (SiO2)) — sedimentary

Jasper

Quartz (SiO2)