Organic (Anthropogenic)

Chert (Jasper)

Microcrystalline Quartz (SiO2) with Iron Oxide inclusions

Chert / Flint

Chert (Cryptocrystalline Quartz, SiO2)

Jasper

Silicon dioxide (SiO2)

Chert / Flint (with quartz or calcite inclusion)

Silicon dioxide (SiO2)

Chert (with Limonite staining)

Microcrystalline Quartz (SiO2)

Dinosaur Fossil (Skull)

Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)

Petrified Wood

Silicified Wood (primarily SiO2)

Chert (specifically Brown Chert or Flint)

Cryptocrystalline Quartz (SiO2)

Fossilized Fish Skeleton in Matrix

Vertebrata (Class: Actinopterygii), typically found in limestone or shale matrices

Petrified Dinosaur Bone (Gembone)

Agatized Dinosaur Bone

Chert (Jasper/Quartzite variety)

Microcrystalline Silica (SiO2)

Chert Pebble

Microcrystalline Quartz (SiO2)

Chert (and/or Flint)

Microcrystalline Quartz (SiO2)

Chert (Iron-stained)

Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Chert (Nodular Chert)

Silicon Dioxide (SiO2)

Pyrite in Limestone

Iron Sulfide (FeS2) in Calcium Carbonate (CaCO3)

Chert (Cherty Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (and Limestone)

Chert (consisting of Microcrystalline Quartz, SiO2)

Chert (Flint)

Microcrystalline Silica (SiO2)

Pearl

Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)

Chert (Field Pebble)

Microcrystalline / Cryptocrystalline Quartz (SiO2)

Chert (and its variety Flint)

Silicon dioxide (SiO2) / Microcrystalline quartz

Chert (Chert Nodule with Cortex)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint)

Microcrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline or cryptocrystalline quartz (SiO2)

Glauconitic Sandstone (Greenstone)

Glauconitic Siliciclastic Sandstone (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2

Chert (specifically Pink Chert or Jasperized Chert)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Pyrite

Iron Sulfide (FeS2)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (specifically Jasper or Flint)

Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variant)

Microcrystalline Quartz (SiO2)

Chert (specifically Red Chert / Jasper)

Silicon Dioxide (SiO2)

Chert (Yellow or Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Yellow Jasper)

Microcrystalline Quartz (SiO2)

Chert (specifically Flint)

Cryptocrystalline Quartz (SiO2)

Chert (and Flint variant)

Chert (SiO2)

Yellow Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Black Jasper

Black Jasper (Silicate mineral - SiO2)

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (SiO2)