Chert (Flint)
Microcrystalline Quartz (SiO2)
Category
Browse organic (non rock) specimens identified by the Rock Identifier community.
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint Jasper
Microcrystalline Quartz (SiO2)
Likely weathered granite or granitic gneiss
Quartz–feldspar–mica rock; possibly gneissic granite
Quartzite Pebble
Metamorphic Quartzite (SiO2)
Diorite
Diorite (intermediate intrusive igneous rock)
Quartzite Cobble
Quartzite (SiO2)
Banded Rhyolite (Wonderstone)
Rhyolite (High-silica volcanic rock)
Quartzite River Rock
Metamorphic Quartzite (SiO2)
Granite
Felsic Plutonic Rock (primarily SiO2)
Fossiliferous Limestone
Carbonate sedimentary rock (CaCO3) with bioclasts
Common Opal with Host Rock
Opal (Hydrated silica, SiO2·nH2O)
Black Limestone with Calcite Veins
Limestone (Calcium Carbonate, CaCO3)
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
Concrete or asphalt-like aggregate surface with a dark fragment
Uncertain; likely artificial concrete containing mixed lithic aggregate, not a natural rock
Hag Stone
Perforated Calcarenite or Chert
Granodiorite (foreground) and Rose Quartz (background)
Granodiorite / Quartz (SiO2)
Granite
Phaneritic Plutonic Felsic Rock
Fossiliferous Limestone
Biogenic Sedimentary Rock (Calcium Carbonate with Fossils)
Jasper
Microcrystalline Quartz (SiO2)
Quartzite
Quartzite (primarily SiO2)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Fossilized tooth, likely a mammalian tooth fragment
Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth
Obsidian
Amorphous volcanic glass (primarily SiO2)
Anthracite Coal
Anthracite (Metamorphic/High-grade Sedimentary Coal)
Glauconitic Sandstone
Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)
Quartzite Pebbles
Quartzite (SiO2)
Quartzite River Rock
Quartzite (primarily SiO2)
Vuggy Limestone
Carbonate Sedimentary Rock with Vuggy Porosity (CaCO3)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Black Flint)
Silicon Dioxide (SiO2)
Black Jasper
Silicon dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert Arrowhead (Lithic Tool)
Microcrystalline quartz (SiO2) - Archeological lithic artifact
Chert Nodule (with Geode cavity)
Cryptocrystalline Quartz (SiO2)
Chert (specifically Flint or Dark Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (varietal: Flint/Jasper mix)
Hydrous Silica (SiO2)
Chert (concretionary/nodular variant)
Microcrystalline Quartz (SiO2) with possible fossil or mineral inclusions
Quartzite
Quartzite (mostly SiO2)
Chert Nodules
Chert (SiO2)
Banded Jasper
Silicate Mineral (Microcrystalline Quartz / SiO2)
Limestone Pebble
Sedimentary carbonate rock (CaCO3)