Obsidian
Volcanic Glass (70-75% SiO2)
igneous
Category
Glass
Browse glass specimens identified by the Rock Identifier community.
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Tektite (Indochinite)
Tektite (High-silica natural glass)
mineraloid
Tektite (Indochinite)
Tektite (High-silica natural glass)
mineraloid
Tektite (Indochinite)
Tektite (High-silica amorphous glass)
igneous
Apache Tear (Obsidian)
Volcanic glass (SiO2 - Silicon Dioxide)
igneous
Obsidian
Volcanic Glass (70% or more SiO2)
igneous
Black Obsidian
Obsidian (Amorphous volcanic glass, SiO2)
igneous
Apache Tear (Obsidian)
Volcanic glass (SiO2 - Silicon Dioxide)
igneous
Pumice
Pumice (Highly vesicular volcanic glass)
igneous
Obsidian
Volcanic Glass (70-75% SiO2)
igneous
Obsidian
Volcanic Glass (Silicon Dioxide with impurities)
igneous
Obsidian
Obsidian (Volcanic Glass, complex silicate)
igneous
Obsidian (Apache Tear)
Volcanic Glass (composed mainly of SiO2)
igneous
Smoky Quartz (Apache Tear Variety)
Silicon dioxide (SiO2) - Volcanic Glass
igneous
Artificial Rock Face (Faux Rock)
Glass Fiber Reinforced Concrete (GFRC)
man-made/construction material
Mahogany Obsidian
Volcanic glass containing Magnetite/Hematite
igneous
Obsidian and Green Calcite
Volcanic Glass and Calcium Carbonate (CaCO3)
igneous and sedimentary/mineral
Tektite
Tektite (high-silica natural glass)
Mineraloid
Scoria (Lava Rock)
Scoria (Vesicular Basaltic Glass/Rock)
igneous
Basalt with vesicles/amygdules
Basalt (containing volcanic glass and plagioclase)
igneous
Opalite
Man-made Glass (SiO2 + additives)
mineraloid (synthetic)
Pumice
Pumice (a highly vesicular volcanic glass)
igneous
Obsidian
Obsidian (Volcanic Glass), primarily SiO2
igneous
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
igneous
Pumice
Pumice (volcanic glass with vesicular texture)
igneous
Indochinite Tektite
Tektite (high-silica impact glass)
igneous
Obsidian Arrowhead
Volcanic Glass (Primary composition: SiO2)
igneous
Black Obsidian
Obsidian (Volcanic glass), 70–75% SiO2
igneous
Obsidian
Obsidian (principally SiO2)
igneous
Milky Quartz
Silicon dioxide (SiO2)
mineral
Quartz Sand Grain
Silicon Dioxide (SiO2)
mineral
Quartz (White/Milky Pebble)
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Milky Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Pearl (Cultured or Natural)
Aragonite (CaCO3) with Conchiolin
Organic Mineraloid
Basalt
Extrusive Mafic Igneous Rock (composed primarily of Plagioclase, Pyroxene, and Olivine)
igneous
Iron Slag
Anthropogenic pyrometallurgical byproduct
igneous
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz Pebble
Silicon Dioxide (SiO2)
mineral