Snowflake Obsidian
Volcanic Glass (spherulitic Obsidian) - SiO2 (with Cristobalite inclusions)
Category
Browse synthetic glass specimens identified by the Rock Identifier community.
Snowflake Obsidian
Volcanic Glass (spherulitic Obsidian) - SiO2 (with Cristobalite inclusions)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz Crystal
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz (with Chlorite/Mineral Inclusions)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon dioxide (SiO2)
River Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
White Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz Crystal
Silicon dioxide (SiO2)
Amethyst
Silicon dioxide with iron impurities (SiO2 + Fe3+)
Milky Quartz
Silicon Dioxide (SiO2)
Polished mahogany obsidian (probable)
Volcanic glass; chiefly rhyolitic silica-rich glass (SiO₂), compositionally near rhyolite
Quartz
Silicon Dioxide (SiO2)
Quartzite Pebbles
Quartzite (primarily SiO2)
Flesh-colored Quartzite
Quartzite (SiO2)
Muscovite Mica
Muscovite (KAl₂(AlSi₃O₁₀)(F,OH)₂))
Vesicular volcanic rock, likely weathered pumice or scoria
Pumice/scoria; predominantly volcanic glass and feldspar, with possible iron oxides
Mahogany Obsidian
Volcanic Glass (SiO2 with Fe/Mg oxides)
Snowflake Obsidian
Volcanic glass containing Spherulitic Cristobalite (SiO2)
Pumice
Pumice (Vesicular Rhyolite/Andesite)
Snowflake Obsidian
Vitreous Volcanic Glass (Siliceous Obsidian with Cristobalite inclusions)
Pumice
Pumice (a highly vesicular extrusive igneous rock)
Polished Basalt
Basalt (Mafic volcanic rock)
Black Obsidian with white veins
Volcanic Glass (70–75% SiO2)
Yellow Aventurine
Quartz (Silicon Dioxide) with Mica inclusions (SiO2)
Chert (specifically Flint or Common Chert)
Chert (Cryptocrystalline Silica, SiO2)
Quartz
Silicon Dioxide (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2) with trace Iron
Quartz
Silicon Dioxide (SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2 with Iron impurities)
Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Fulgurite
Lechatelierite (Fulgurite / Petrified Lightning)
Weathered quartz-rich river cobble, possibly quartzite
Quartzite (mostly microcrystalline SiO₂), tentatively identified
Orange Quartzite
Quartzite (SiO2 with iron oxide impurities)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)