Slag Glass
Anthropogenic Amorphous Silicon Dioxide
Category
Browse glass specimens identified by the Rock Identifier community.
Slag Glass
Anthropogenic Amorphous Silicon Dioxide
Goldstone
Aventurine Glass (Man-made)
Rounded quartz-rich pebble (likely vein quartz or quartzite)
Quartz, silicon dioxide (SiO₂); possibly quartzite if metamorphic
Polished blue-green glassy slag or coated mineral fragment
Most likely man-made colored glass/slag; exact composition cannot be determined visually
Milky Quartz/Clear Quartz Cluster
Silicon Dioxide (SiO2)
Quartz (Grain/Fragment)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Blue glassy fragment among beach gravel
Likely cobalt-blue man-made glass; not a natural mineral specimen
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2)
Chert Nodules in Limestone
Microcrystalline Quartz (SiO2) in Carbonate Matrix
Chert (Flint)
Microcrystalline Quartz (SiO2)
Citrine Quartz
Silicon Dioxide (SiO2) with trace Iron impurities
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert / Red Jasper
Microcrystalline Quartz (SiO2)
Quartz
Silicon Dioxide (SiO2)
Chert (Flint)
Chert (SiO2)
Quartz
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Green Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2 + K(Al,Cr)2AlSi3O10(OH)2
Pumice
Pumice (Vesicular Felsic Igneous Rock)
Quartz Crystal with Inclusions
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2 with iron impurities)
Clear Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Chert / Flint
Chert (Microcrystalline Quartz, SiO2)
Green Aventurine
Aventurine Quartz (SiO2) with Fuchsite inclusions
Quartz (Milky or Citrine-tinted)
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Opalite crescent pendant
Opalite (man-made opalescent glass; not a natural mineral)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartz
Silicon Dioxide (SiO2)
Quartz Pebble (Iron-Stained)
Quartz (Silicon Dioxide - SiO2)
White quartz bead bracelet (likely milky quartz)
Quartz, silicon dioxide (SiO₂), usually microcrystalline or cloudy crystalline quartz
Milky quartz (likely quartz-rich fragment)
Quartz, silicon dioxide (SiO₂)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz Pebble (Chert/Chalcedony)
Silicon Dioxide (SiO2)
Sea Glass
Man-made vitreous material (silica-based glass)
Sea Glass
Man-made silicate glass (Amorphous silicon dioxide)
Sea Glass
Amorphous Silicon Dioxide (Man-made glass weathered by nature)