Pumice
Pumice (a highly vesicular volcanic glass)
igneous
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
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Basalt Pebble
Extrusive Igneous Rock
igneous
Pumice
Pumice (volcanic glass formed of highly vesicular rough textured rock)
igneous
Obsidian
Volcanic glass (Amorphous silicon dioxide)
igneous
Red scoria (vesicular basalt)
Scoriaceous basalt; chiefly plagioclase, pyroxene, and iron-rich volcanic glass
igneous
Pumice
Vesicular Felsic Extrusive Igneous Rock
igneous
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
igneous
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide)
igneous
Dark gray weathered pebble, likely basalt
Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides
igneous
Blue Obsidian
Volcanic Glass (SiO2 with inclusions)
igneous
Amethyst (Rough)
Silicon Dioxide with iron impurities (SiO2)
mineral
Pumice
Pumice (a highly vesicular felsic volcanic rock)
igneous
Amethyst
Amethyst (Silicon Dioxide - SiO2)
mineral
Snowflake Obsidian (or similar porphyritic volcanic rock)
Obsidian with Spherulites (if glassy), or Porphyritic Rhyolite/Andesite (if crystalline groundmass)
igneous
Vesicular volcanic rock, likely weathered pumice or scoria
Pumice/scoria; predominantly volcanic glass and feldspar, with possible iron oxides
igneous
Snowflake Obsidian
Volcanic Glass with Spherulite Inclusions (primarily SiO2)
igneous
Pumice
Vesicular volcanic glass (primarily Alumino-silicates)
igneous
Scoria (Lava Rock)
Vesicular Basalt / Scoria
igneous
Pumice
Pumice (volcanic glass with vesicular texture)
igneous
Pumice
Pumice (a highly vesicular amorphous volcanic glass)
igneous
Basalt
Extrusive igneous rock
igneous
Basalt
Extrusive Igneous Rock
igneous
Basalt
Extrusive Igneous Rock
igneous
Basalt
Extrusive Igneous Rock
igneous
Pumice
Pumice (a highly vesicular volcanic glass)
igneous
Black Obsidian
Obsidian (Volcanic glass), 70–75% SiO2
igneous
Agate
Silicon Dioxide (Chalcedony), SiO2
sedimentary
Pumice
Vesicular Rhyolite or Andesite (Amorphous volcanic glass)
igneous
Slag (Industrial Glass/Glassy Rock)
Anthropogenic Vitreous Material
igneous
Obsidian
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
igneous
Basalt
Extrusive Igneous Rock
igneous
Polished porphyritic basalt (likely)
Basalt, a fine-grained mafic volcanic rock; visible inclusions may be olivine, feldspar, or vesicle infillings
igneous
Pumice
Pumice (volcanic glass with vesicular texture)
igneous
Quartz Druzy (on Geode Fragments)
Silicon Dioxide (SiO2)
mineral
Snowflake Obsidian
Volcanic glass containing Cristobalite (SiO2)
igneous
Basalt
Extrusive igneous rock
igneous
Basalt
Extrusive mafic igneous rock
igneous
Basalt
Mafic extrusive igneous rock
igneous
Pumice
Pumice (a highly vesicular volcanic glass)
igneous
Pumice
Pumice (Volcanic glass / Silicic extrusive rock)
igneous
Vesicular basalt (probable)
Basalt; chiefly plagioclase feldspar, clinopyroxene, and iron-rich minerals, with vesicles possibly lined by zeolites or calcite
igneous
Porphyritic Basalt or Porphyritic Andesite
Porphyritic Extrusive Igneous Rock
igneous