Quartzite
Quartzite (SiO2)
Category
Browse organic (non rock) specimens identified by the Rock Identifier community.
Quartzite
Quartzite (SiO2)
Chert (Basanite / Jasperoid)
Microcrystalline Quartz (SiO2)
Chert (Green Chert)
Microcrystalline silica (SiO2)
Fossiliferous Limestone
Biogenic Sedimentary Rock / CaCO3 with fossil fragments
Limestone pebble
Sedimentary rock, primarily calcium carbonate (CaCO3)
Apache Tear (Obsidian)
Obsidian (Hydrated Amorphous Silica, SiO2 + MgO/Fe3O4)
Bull Quartz
Quartz (Silicon Dioxide - SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Baltic Amber (Butterscotch variety)
Succinite
Anthracite Coal
Anthracite (Carbon Content: 86%-97%)
Graphite Schist
C (Carbonaceous Schist)
Quartzite
Quartzite (SiO2)
Polished orbicular granite (likely larvikite or orbicular diorite)
Quartz/feldspar-bearing granitoid with dark amphibole–biotite minerals; exact variety requires testing
Quartz Geode
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Obsidian (Volcanic Glass, primarily SiO2)
Crushed Limestone
Sedimentary Calcite/Dolomite Rock (CaCO3)
Chert (River Pebble)
Cryptocrystalline Quartz (SiO2)
Slag (Industrial Byproduct)
Anthropogenic Vitreous Silicate material
Conglomerate
Clastic sedimentary rock (Conglomerate)
Pyrite Geode (Sparkling Druzy)
Iron Sulfide (FeS2) in Sedimentary Nodule
Pearl necklace
Pearl (biogenic calcium carbonate, chiefly aragonite; CaCO₃)
Jasper
Silicon Dioxide (Microcrystalline Quartz, $SiO_2$)
Grey Chert River Pebble
Microcrystalline Quartz (SiO2)
Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2
Red Jasper
Silicon dioxide (SiO2) with iron oxide (Fe2O3) inclusions
Sandstone
Arenite
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varietal Chalcedony or Flint)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Chert Pebble
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Agate variety)
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica/Amphibole)
Sandstone (likely a river or beach pebble)
Sandstone (a clastic sedimentary rock)
Travertine
Calcareous Tufa / Travertine (CaCO3)
Chert (Jasper/Agate mix)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Quartzite
Quartzite
Yellow Chert
Sedimentary cryptocrystalline quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Fossiliferous Limestone
Fossiliferous Limestone (Sedimentary Rock)
Dalmatian jasper
Orbicular microcrystalline quartz rock, commonly rhyolitic or volcanic-feldspar matrix with black arfvedsonite/alkali-amphibole inclusions