Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse non geological specimens identified by the Rock Identifier community.
Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Obsidian
Amorphous volcanic glass (principally SiO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Bull Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Obsidian
Volcanic Glass
Obsidian with Mahogany Phasing
Volcanic Glass (SiO2 + Fe2O3)
Polished quartz-rich pebble, possibly jasper or quartzite
Quartzite or chalcedony-bearing jasper; predominantly SiO₂
Snowflake Obsidian
Obsidian with Cristobalite inclusions (mostly amorphous SiO2)
Limestone
Calcium Carbonate (CaCO3)
Opalite
Man-made Synthetic Glass (Silicon Dioxide with metal additives)
Obsidian
Volcanic glass (primary composition: SiO2)
Quartzite
Metamorphic Quartz Rock (SiO2)
Black Obsidian
Obsidian (Volcanic Glass, rich in SiO2)
Obsidian
Volcanic Glass (SiO2)
Tektite (Indochinite)
Tektite (Lechatelierite-rich silica glass)
Anthracite Coal
Anthracite
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurity)
Green glass sphere/marble
Soda-lime glass (primarily SiO2, Na2O, CaO)
Grey River Stone (Quartz-rich Quartzite/Siltstone)
Quartzite / Meta-siltstone (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Volcanic Glass (SiO2)
Biotite Mica in Host Rock
Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)
Obsidian
Obsidian (Volcanic Glass)
Ferrosilicon Slag (Industrial Vitrified Glass)
Vitreous Silicate Residue
Black Obsidian
Volcanic Glass (SiO2 with impurities)
Cullet Glass (Man-made Glass Slag)
Amorphous Silica (SiO2) with chemical additives
Black Obsidian
Obsidian (Volcanic Glass, ~70% SiO2)
Quartzite
Quartzite (chiefly SiO2)
Slag (Industrial Byproduct)
Anthropogenic Vitreous Silicate material
Quartzite
Quartzite (primarily SiO2)
Quartzite
Quartzite (SiO2)
Siltstone River Pebble
Siltstone (primarily composed of silt-sized particles)
Obsidian
Obsidian (Volcanic Glass)
Man-made Crystal (Lead Glass)
Lead oxide-doped Silica Glass (approx. SiO2 + PbO)
Obsidian
Obsidian (Volcanic glass), 70-75% SiO2
Quartzite
Metamorphic Quartzite (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
N/A (Non-Geological Object)
Quartzite
Quartzite (SiO2)
Siltstone with Quartz Vein
Siltstone (primarily SiO2, Al2O3, Fe2O3)
Quartzite
Metamorphic Quartzite (SiO2)