Quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly crystalline quartz (SiO₂), possibly with mica and feldspar
Category
Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.
Quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly crystalline quartz (SiO₂), possibly with mica and feldspar
Amethyst (Raw Quartz)
Silicon Dioxide (SiO2) with iron impurities
Chert / Flint
Silicon Dioxide (SiO2)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions (SiO2)
Mixed Tumbled Quartz and Chlorite Quartz
Silicon Dioxide (SiO2) with inclusions
Muscovite Mica
KAl2(AlSi3O10)(F,OH)2
Snowflake Obsidian
Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)
Muscovite Mica (with Quartz matrix)
Muscovite - KAl2(AlSi3O10)(OH)2
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Fulgurite
Fulgurite (Lechatelierite or fused sand/quartz)
Chert (Flint/Jasper)
Silicon Dioxide (SiO2)
Quartz (Clear Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Snowflake obsidian cabochon
Obsidian (volcanic glass), SiO₂-rich; white areas are cristobalite/spherulitic devitrification
Obsidian
Obsidian (Volcanic Glass)
Chert (Flint Gravel)
Silicon Dioxide (SiO2)
Tumbled reddish sandstone pebble
Quartz-rich sandstone, likely ferruginous arkose or quartz arenite
Tumbled Quartz Pebble
Silicon Dioxide (SiO2)
Red Quartz (Tumbled)
Silicon Dioxide with Iron Oxide inclusions (SiO2)
Obsidian
Volcanic Glass (SiO2 + minor impurities)
Botryoidal quartz (likely milky quartz)
Quartz, silicon dioxide (SiO₂)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Snowflake Obsidian
Volcanic Glass (spherulitic obsidian)
Sea Glass
Amorphous silicon dioxide (glass)
Prasiolite (Green Quartz) / Sea Glass Amalgam
SiO2 (Silicon Dioxide)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Green Aventurine
Quartz (Silicon Dioxide, SiO2) with fuchsite inclusions
Snowflake Obsidian
Obsidian with Cristobalite inclusions (70-75% SiO2)
Quartz (Milky/Clear variety)
Silicon Dioxide (SiO2)
Milky quartz pebble
Quartz (silicon dioxide, SiO₂)
Muscovite Mica
KAl2(AlSi3O10)(OH)2
Muscovite (Mica)
Muscovite - KAl2(AlSi3O10)(OH)2
Muscovite Mica
Muscovite - KAl2(AlSi3O10)(OH)2
Clear Quartz
Silicon Dioxide (SiO2)
Amethyst Quartz fragment
SiO2 (Silicon Dioxide with Iron impurities)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert or Chalcedony
Microcrystalline Quartz (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Slag Glass
Amorphous Silica / Glass Slag
Weathered quartz-rich rock, possibly pegmatite or quartzite
Quartz (SiO₂)-rich aggregate; exact identification is uncertain from the photograph