Organic (Biological Organism)

Petrified Wood

Silicified Wood (SiO2)

Pearl (with Peridot)

Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4

Mookaite (Mookaite Jasper)

Silicified Radiolarite (SiO2 with iron oxides)

Chert (Brown variety / Common Jasper)

Microcrystalline Quartz (SiO2)

Red Jasper

Jasper (Silicon Dioxide with Iron inclusions - SiO2)

Anthracite Coal

Anthracite

Chert (variously identified as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Septarian Nodule (Thunder Egg)

Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)

Amber Flint (Chert)

Cryptocrystalline Quartz (Silicon Dioxide, SiO2)

Chert (varietal Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (Tan/Grey variety)

Silicon Dioxide (SiO2)

Sandstone (likely with Borings or Vesicular Basalt)

Clastic Sedimentary Rock (Sandstone)

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Chert (often called Flint or Jasper locally)

Chert (Microcrystalline Quartz, Formula: SiO2)

Petrified Wood

Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Fossiliferous Chert (with Brachiopod or Mollusk fragments)

Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions

Limestone with Quartz/Calcite Veins

Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)

Mookaite Jasper

Silicified Radiolarite (SiO2)

Coral Fossil (Petrified Coral)

Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)

Jasper (specifically Yellow Jasper and Red Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

Banded Chert (with Quartz Vein)

Microcrystalline Silica (SiO2)

Anthracite Coal

Anthracite (Carbon-rich metamorphic coal)

Chert (Chert Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)

Silicon Dioxide (SiO2)

Travertine (often colloquially called Tufa)

Chemical Sedimentary Calcium Carbonate (CaCO3)

Chert (specifically Iron-stained River Cobble)

Silicon Dioxide (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Green Banded Chert (Agate/Jasper)

Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite

Coquina

Biogenic Limestone (Calcium Carbonate, CaCO3)

Graphite

Graphite (Native Carbon, C)

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert (Cherty Flint/Jasper variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Fossiliferous Chert (Gryphaea Fossil)

Silicon Dioxide (SiO2) with Calcitic Mollusk Remnants

Septarian Nodule or Mud Crack Fossil

Septarian Nodule (Concretion)

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

Jasper

Agate/Jasper (Microcrystalline Quartz, SiO2)