Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic (biological specimen) specimens identified by the Rock Identifier community.
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Fossilized Coral
Scleractinian Anthozoa (Fossilized Calcium Carbonate, CaCO3)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (Silicon Dioxide - SiO2)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varietal: Flint or River Pebble)
Silicon Dioxide (SiO₂)
Chert (Jasper/Agate variety)
Silicon Dioxide (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Pink Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O)
Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert / Jasper
Microcrystalline Quartz (SiO2)
Chert (varieties include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (Quartz, SiO2)
Travertine
Calcareous Tufa (CaCO3)
Chert (specifically a stream-worn Chert Nodule)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (often called Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Amber
Succinite (specifically for Baltic amber; fossilized tree resin)
Fossil Coral
Scleractinia (Fossilized Coral) / Calcium Carbonate (CaCO3) or Silica (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Brachiopod Fossil in Limestone
Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)
Chert (Black Chert or Flint)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Chert (Pebble)
Silicon Dioxide (SiO2)
Anthracite Coal
Anthracite (Carbon based fossil fuel)
Chert (Flint)
Silicon Dioxide (SiO2)
Red Jasper (possibly Petrified Wood)
Silicon Dioxide (SiO2) with Hematite inclusions
Amber
Succinate (Fossilized Tree Resin)
Chert (with Limestone/Dolomite host)
Microcrystalline Quartz (SiO2)
Shale
Shale (Sedimentary rock composed of mud/clay minerals)
Amber
Succinite (organic gemstone, approx. C10H16O)
Shale
Mudrock / Fissile Shale
Pink Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Limestone
Calcium Carbonate (CaCO3)
Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)