Rock Identifier

Category

Volcanic Glass (Igneous)

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

Learn about Volcanic Glass (Igneous) in the encyclopedia

Black Obsidian

Pink Obsidian

Sideromelane

Obsidian

Tachylite

Perlite

Yellow Obsidian

Yellow Obsidian

Turquoise Obsidian

Teal Obsidian

Green Sheen Obsidian

Clear Obsidian

Cobalt Blue Obsidian

Possible industrial slag or basaltic volcanic glass (Likely iron-rich vitreous slag; natural alternative: basaltic glass (tachylite)) — igneous

Possible industrial slag or basaltic volcanic glass

Likely iron-rich vitreous slag; natural alternative: basaltic glass (tachylite)

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

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Pumice (Pumice (Vesicular Rhyolite/Andesite)) — igneous

Pumice

Pumice (Vesicular Rhyolite/Andesite)

Snowflake Obsidian (Volcanic Glass with Cristobalite inclusions) — igneous

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions

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

Pumice

Pumice (a highly vesicular volcanic glass)

Polished black obsidian (Volcanic glass; predominantly rhyolitic silica glass (approximately SiO₂-rich)) — igneous

Polished black obsidian

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

Polished black stone, likely black obsidian (Obsidian (volcanic glass; mainly SiO₂)) — igneous

Polished black stone, likely black obsidian

Obsidian (volcanic glass; mainly SiO₂)

Possible tumbled obsidian (Volcanic glass, primarily rhyolitic silica glass (SiO₂-rich)) — igneous

Possible tumbled obsidian

Volcanic glass, primarily rhyolitic silica glass (SiO₂-rich)

Green obsidian (likely molded or heat-treated glass-like specimen) (Volcanic glass; predominantly rhyolitic composition (silica-rich amorphous SiO₂)) — igneous

Green obsidian (likely molded or heat-treated glass-like specimen)

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

Obsidian (likely volcanic glass) (Obsidian; amorphous rhyolitic volcanic glass, typically rich in SiO₂) — igneous

Obsidian (likely volcanic glass)

Obsidian; amorphous rhyolitic volcanic glass, typically rich in SiO₂

Rhyolite (Rhyolite) — igneous

Rhyolite

Rhyolite

Obsidian (Obsidian) — igneous

Obsidian

Obsidian

Pumice (Pumice (Vesicular volcanic glass)) — igneous

Pumice

Pumice (Vesicular volcanic glass)

Vesicular volcanic rock (likely pumice) (Pumice, a highly vesicular volcanic glass; exact identification is uncertain from the image) — igneous

Vesicular volcanic rock (likely pumice)

Pumice, a highly vesicular volcanic glass; exact identification is uncertain from the image

Obsidian (Volcanic Glass (Amorphous SiO2)) — igneous

Obsidian

Volcanic Glass (Amorphous SiO2)

Pumice (Vesicular volcanic glass, typically rhyolitic to dacitic; mainly silica-rich volcanic glass with feldspar and minor quartz or pyroxene) — igneous

Pumice

Vesicular volcanic glass, typically rhyolitic to dacitic; mainly silica-rich volcanic glass with feldspar and minor quartz or pyroxene

Obsidian (Volcanic Glass (Amorphous SiO2)) — igneous

Obsidian

Volcanic Glass (Amorphous SiO2)

Snowflake Obsidian (Spherulitic Volcanic Glass (primarily SiO2)) — igneous

Snowflake Obsidian

Spherulitic Volcanic Glass (primarily SiO2)

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

Black Obsidian

Obsidian (Volcanic Glass, SiO2+)

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

Pumice

Pumice (a vesicular volcanic glass)

Snowflake Obsidian (Obsidian with Cristobalite inclusions (SiO2)) — igneous

Snowflake Obsidian

Obsidian with Cristobalite inclusions (SiO2)

Pumice (Pumice (Felsic vesicular volcanic glass)) — igneous

Pumice

Pumice (Felsic vesicular volcanic glass)

Obsidian (likely black volcanic glass) (Obsidian; naturally occurring rhyolitic glass, primarily SiO₂) — igneous

Obsidian (likely black volcanic glass)

Obsidian; naturally occurring rhyolitic glass, primarily SiO₂

Snowflake obsidian cabochon (Obsidian (volcanic glass), SiO₂-rich; white areas are cristobalite/spherulitic devitrification) — igneous

Snowflake obsidian cabochon

Obsidian (volcanic glass), SiO₂-rich; white areas are cristobalite/spherulitic devitrification

Snowflake Obsidian (Hydrated Volcanic Glass with Cristobalite inclusions) — igneous

Snowflake Obsidian

Hydrated Volcanic Glass with Cristobalite inclusions

Obsidian (black volcanic glass), possibly with brecciated or weathered fragments (Obsidian; predominantly rhyolitic volcanic glass, typically rich in SiO₂) — igneous

Obsidian (black volcanic glass), possibly with brecciated or weathered fragments

Obsidian; predominantly rhyolitic volcanic glass, typically rich in SiO₂

Tumbled obsidian (Volcanic glass; chiefly SiO₂, noncrystalline) — igneous

Tumbled obsidian

Volcanic glass; chiefly SiO₂, noncrystalline

Snowflake obsidian (Volcanic glass (obsidian), chiefly silica-rich rhyolitic composition, with cristobalite or feldspar spherulites) — igneous

Snowflake obsidian

Volcanic glass (obsidian), chiefly silica-rich rhyolitic composition, with cristobalite or feldspar spherulites

Obsidian (black volcanic glass) (Obsidian; predominantly rhyolitic volcanic glass, mainly SiO₂ with minor feldspar, quartz, and iron oxides) — igneous

Obsidian (black volcanic glass)

Obsidian; predominantly rhyolitic volcanic glass, mainly SiO₂ with minor feldspar, quartz, and iron oxides

Mahogany Obsidian (Volcanic Glass with Hematite or Magnetite inclusions (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite or Magnetite inclusions (SiO2 + Fe2O3)

Obsidian (Extrusive igneous volcanic glass (rich in SiO2)) — igneous

Obsidian

Extrusive igneous volcanic glass (rich in SiO2)

Pumice (Pumice (SiO2 + Al2O3 + Fe2O3)) — igneous

Pumice

Pumice (SiO2 + Al2O3 + Fe2O3)

Obsidian (Volcanic Glass (Mainly SiO2)) — igneous

Obsidian

Volcanic Glass (Mainly SiO2)

Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

Polished black stone, likely obsidian (Obsidian — natural volcanic glass, compositionally silica-rich (typically rhyolitic)) — igneous

Polished black stone, likely obsidian

Obsidian — natural volcanic glass, compositionally silica-rich (typically rhyolitic)

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

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

Tumbled black stone, likely black obsidian (Obsidian (volcanic glass; chiefly silica-rich rhyolitic composition)) — igneous

Tumbled black stone, likely black obsidian

Obsidian (volcanic glass; chiefly silica-rich rhyolitic composition)

Pumice (Pumice (Amorphous volcanic glass)) — igneous

Pumice

Pumice (Amorphous volcanic glass)

Obsidian (black volcanic glass), possibly slag or basalt (Obsidian; chiefly amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition) — igneous

Obsidian (black volcanic glass), possibly slag or basalt

Obsidian; chiefly amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Polished black stone, likely basalt or basaltic glass (Fine-grained basalt (possibly devitrified volcanic glass); mainly plagioclase and pyroxene, with iron-titanium oxides) — igneous

Polished black stone, likely basalt or basaltic glass

Fine-grained basalt (possibly devitrified volcanic glass); mainly plagioclase and pyroxene, with iron-titanium oxides

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

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

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

Pumice

Vesicular volcanic glass (primarily SiO2)