Anthropogenic Material (Man Made Sedimentary Mimic)

Chert (Jasper/Flint variation)

Chert (SiO2)

Chert (often called Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Banded Calcite (often marketed as 'Mexican Onyx')

Calcite (Calcium Carbonate, CaCO3)

Chert (Honey Chert / Flint)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Chert (and Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (variously known as Flint or River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Calcite (Cave Onyx)

Calcium Carbonate (CaCO3)

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)

Chert (specifically Tan Chert or Flint)

Silicon Dioxide (SiO2)

Sandstone

Sandstone (clastic sedimentary rock)

Sandstone (specifically Arkose or Ferruginous Sandstone)

Sandstone (SiO2 with iron oxide inclusions)

Banded Flint (Chert)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Yellow Jasper

Jasper, a microcrystalline variety of Quartz (SiO2) with iron inclusions

Red Jasper

Silicon Dioxide (SiO2)

Chert

Microcrystalline Quartz (SiO2)

Fossiliferous Limestone (Coquina / Shell Limestone)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Coquina

Biogenic Limestone (Coquina)

Grey River Pebble (Likely Quartz-rich or Limestone)

Clastic Sedimentary Rock (typically SiO2 or CaCO3 based)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 staining)

Chert (often called Flint or River Stone)

Microcrystalline Quartz (SiO2)

Banded Iron Formation (BIF)

Banded Iron Formation (Magnetite-Hematite-Chert)

Red Sandstone

Arenite (primarily Quartz with Iron Oxide)

Mookaite Jasper

Silicified Radiolarite (SiO2 with impurities)

Sandstone (Ferruginous)

Arenite with Iron-Oxide Cement

Chert (Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Sandstone

Arenite (primarily SiO2)

Siltstone

Siltstone (composed of microscopic silt-sized particles of quartz and feldspar)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (primarily SiO2 with various cementing agents)

Travertine

Calcareous Tufa / Travertine (CaCO3)

Chert (often called Flint in various colors)

Silicon Dioxide (SiO2)

Chert

Microcrystalline Quartz (SiO2)

Quartz

Quartz (SiO2, Silicon Dioxide)

Sandstone

Clastic Sedimentary Rock (composed mostly of SiO2)

Sandstone

Sandstone (lithified quartz arenite, arkose, graywacke, etc. depending on composition)

Fossil Coral (Rugose Coral Fragment)

Rugosa (extinct order of solitary and colonial corals)

Sandstone (Ferruginous/Red Sandstone)

Clastic sedimentary rock (primarily SiO2 with Fe2O3)

Chert (Nodular Chert)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)