Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of cellulose)
Category
Browse organic material specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of cellulose)
Chert (variations like Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert Nodule (Flint)
Chert (Silicon Dioxide, SiO2)
Chert (often called Flint)
Microcrystalline to cryptocrystalline quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Bioclastic Limestone (CaCO3)
River-worn Chert
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Carbonate Sedimentary Rock (primarily CaCO3)
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Banded Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Mother of Pearl and Onyx
Aragonite (Mother of Pearl) and Chalcedony (Onyx)
Travertine (Tufa)
Travertine (Aragonite/Calcite form of Calcium Carbonate, CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Coquina / Shell Limestone
Coquina (Bioclastic Limestone)
Chert (Black Chert or Flint)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Pink shell fragment
Calcium carbonate, likely aragonite or calcite (CaCO₃); probably a bivalve or gastropod shell fragment
Likely tumbled yellow calcite or limestone fragment
Calcite (CaCO₃), possibly micritic limestone
Chert (Flint)
Chert (Cryptocrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Flint)
Silicon dioxide (SiO2) - Microcrystalline Quartz
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (specifically a Chert Nodule or Flint)
Cryptocrystalline Quartz (SiO2)
Tumbled petrified wood
Silicified wood; primarily microcrystalline quartz (SiO₂)
Petrified Wood
Silicified Wood (primarily SiO2)
Sandstone
Arenite
Chert (White Flint)
Microcrystalline Quartz (SiO2)
Chert (specifically Flint)
Silicon Dioxide (SiO2)
Fossilized Coral (Petrified Coral)
Lithostrotionella (example genus) / Scleractinia
Chert Pebble
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement)
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
Chert (Jasper/Common Opal mix)
Microcrystalline Quartz (SiO2)
Chert (Black Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
Flint or chert, possibly a knapped stone tool
Microcrystalline quartz (SiO₂), commonly chalcedony with possible carbonaceous impurities