Sandstone
Arenite (SiO2 primarily)
Category
Browse man made glass specimens identified by the Rock Identifier community.
Sandstone
Arenite (SiO2 primarily)
Gemstone bead necklace (likely citrine or yellow quartz)
Quartz, SiO₂; precise identification is uncertain because the beads are blurred and metal settings obscure them
Sandstone
Sedimentary Rock (Quartz arenite)
Sandstone (likely Quartzose)
Clastic sedimentary rock (SiO2 primary)
Chert
Microcrystalline quartz (SiO2)
Chert (Flint / Jasper variant)
Microcrystalline Quartz (SiO2)
Engraved purple stone cabochon, possibly amethyst
Unconfirmed; if amethyst, quartz (SiO₂)
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
Quartzite
Metamorphic Quartzite (SiO2)
Quartzite pebble
Quartzite (SiO2)
Tumbled gray chalcedony (likely agate or quartzite)
Microcrystalline quartz, SiO₂ (chalcedony)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Granite
Felsic intrusive igneous rock
Chert Nodule
Microcrystalline Quartz
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
Smoky Quartz
Silicon Dioxide (SiO2)
Brown Chert
Microcrystalline Quartz (SiO2)
Chert (Flint)
Chert (SiO2)
Faceted clear gemstone in a gold-tone ring, likely colorless glass or cubic zirconia
Undetermined; possible cubic zirconia (ZrO₂) or glass (amorphous SiO₂)
Tumbled chalcedony (likely milky quartz)
Microcrystalline quartz, SiO₂; possibly pale agate or quartzite
Chert (Quartz Variety)
Chert (Silicon Dioxide, SiO2)
Chert (Black Flint)
Silicon Dioxide (SiO2)
Chert / Flint
Microcrystalline Quartz (SiO2)
Chert (Common Opal/Jasper variety)
Cryptocrystalline Quartz (SiO2)
Sandstone (specifically Arkose or Quartz Arenite)
Arenite (primarily SiO2 with possible Feldspar)
Milky quartz
Quartz, silicon dioxide (SiO₂)
Chert (Flint)
Silicon Dioxide (SiO2)
Granite
Phaneritic Felsic Igneous Rock
Likely banded obsidian or dark volcanic glass
Obsidian, predominantly rhyolitic volcanic glass (SiO₂-rich), possibly with devitrified bands and phenocrysts
Sandstone
Arenite (variable SiO2 composition)
Green aventurine (likely), shaped star
Quartz, SiO₂, with green fuchsite inclusions
Goldstone
Not a natural mineral or rock. It is an ornamental glass.
Sandstone
Arenite (composed primarily of SiO2)
Chert (Flint Nodules)
Cryptocrystalline Quartz (SiO2)
Ferrosilicon Slag (Industrial Vitrified Glass)
Vitreous Silicate Residue
Chert (Chocolate or Brown Flint)
Chert (SiO2)
Sandstone
Sedimentary Rock (Quartz Sandstone)
Chert (Flint/Chalcedony)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (primarily SiO2)
Green gemstone ring (likely synthetic or imitation emerald)
Possibly emerald, beryl (Be₃Al₂Si₆O₁₈); the photo cannot confirm the center stone’s identity or whether it is natural.