Sedimentary (Fossilized Organic Remain)

Chert (often called Flint or River Stone)

Chert (Microcrystalline Silicon Dioxide, SiO2)

Chert (and associated river cobbles)

Silicon dioxide (SiO2)

Chert (Jasper variety)

Chert (SiO2)

Chert (Black Chert/Flint)

Silicon Dioxide (SiO2)

Chert Pebble

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (and Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Moss Agate

Agate (Silicon Dioxide, SiO2) with dendritic inclusions

Chert (with Limestone and Iron Oxide staining)

Cryptocrystalline Quartz (SiO2)

Fossiliferous Limestone (Coquina)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Chert (specifically Pink/Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Arrowhead/Artifact Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Gray/Blue Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert (specifically a Chert Nodule or Flint)

Cryptocrystalline Quartz (SiO2)

Red Chert (Jasper)

Cryptocrystalline Quartz (SiO2) with iron oxide inclusions

Petrified Wood

Silicified Wood (primarily SiO₂ / Silicon Dioxide)

Stromatolite (Fossiliferous Limestone)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Petrified Wood

Silicified wood (primarily Silicon Dioxide, SiO2)

Shale with Pyrite

Clastic sedimentary rock containing Iron Disulfide (FeS2)

Porphyritic Andesite

Porphyritic Andesite (Intermediate Volcanic Rock)

Pink Opal

Amorphous Hydrous Silica (SiO2·nH2O)

Ferruginous Sandstone (Ironstone)

Sedimentary rock with Limonite/Goethite cement

Chert (Grey/Black variety)

Chert (Silicon Dioxide, SiO2)

Chert (often called Flint in this context)

Silicon Dioxide (SiO2)

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Commonly known as Flint or Jasper when pigmented)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Tan/Brown variety)

Chert (Microcrystalline Quartz, SiO2)

Chert (Cherty Limestone or Flint)

Microcrystalline Silica (SiO2)

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (often called Flint or Jasper based on color)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Nodular or Massive Variety)

Cryptocrystalline Quartz (SiO2)

Chert with Quartz/Calcite Vein

Microcrystalline Silica (SiO2)