Chert (Common Opal or Agate)
Microcrystalline Quartz (SiO2)
Category
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Chert (Common Opal or Agate)
Microcrystalline Quartz (SiO2)
Fossil Coral
Cnidaria Anthozoa (Fossilized)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Chert with Fossil Brachiopod
Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion
Chert (Flint)
Microcrystalline Silicon Dioxide (SiO2)
Chert Arrowhead (Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Limestone (Weathered/Silicified)
Sedimentary carbonate rock (primarily CaCO3)
Chert (Yellow Jasper/Flint)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Petrified Wood
Silicified Wood (SiO2)
Gastropod Steinkern (Fossil Snail Internal Mold)
Class Gastropoda (Internal Mold)
Petrified Wood
Silicified Wood (SiO2)
Chert (or Flint)
Chert (Sedimentary Cryptocrystalline Sio2)
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
Chert (Nodule/Pebble)
Chert (Silicon Dioxide, SiO2)
Chert (Jasper)
Silicon dioxide (SiO2)
Chert Pebble Map
Microcrystalline Quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Fossil Shell (Brachiopod or Mollusk)
Phylum Brachiopoda or Class Bivalvia (e.g., Mucrospirifer or similar genus)
Unidentified weathered rock fragment
Indeterminate; possibly vesicular basalt or weathered volcanic rock
Conglomerate
Conglomerate
Fossiliferous Limestone
Fossiliferous Carbonate Rock (CaCO3)
Chert (specifically Banded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossiliferous Rock (likely Dinosaur Fossil in Matrix)
Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)
Moss agate bracelet
Chalcedony (microcrystalline quartz, SiO₂) with chlorite/amphibole inclusions
Limestone with Stylolites
Calcareous sedimentary rock (CaCO3)
Chert
Cryptocrystalline Quartz (SiO2)
Chert (Red Jasper variant)
Microcrystalline Quartz (SiO2)
Graphite-veined Quartzite
Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)
Shale with Vein Infillings
Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.
Bituminous Coal
Coal (Organically derived sedimentary rock)
Stromatolite
Biogenic Sedimentary Rock (composed predominantly of CaCO3)
Chert (Jasper/Chalcedony mix)
Microcrystalline Quartz (SiO2)
Limestone (River Pebble)
Calcium Carbonate (CaCO3)
Green Chert
Microcrystalline Quartz (SiO2)
Quartz Geode in Chert/Limestone Matrix
Silicon Dioxide (SiO2) within Sedimentary Host Rock
Fossiliferous Limestone
Calcite-rich Fossiliferous Limestone (CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Limestone pebble
Sedimentary rock, primarily calcium carbonate (CaCO3)
Amber
Succinite (Approximate formula: C10H16O)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)