Organic (Biological Specimen)

Ambergris (Geological/Organic Specimen)

Ambra grisea (Produced by Physeter macrocephalus)

Banded Chert

Cryptocrystalline Quartz (SiO2)

Chert (Nodule / Geode fragment)

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline silicon dioxide (SiO2)

Chert (Quartz Pebble)

Silicon Dioxide (SiO2)

Chert / Quartz Pebble

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Jasper (Petrified Wood Variety)

Silicon Dioxide (SiO2)

Moss Agate

Silicon Dioxide (SiO2) with inclusions

Fossiliferous Limestone with Rugose Coral

Calcium Carbonate (CaCO3) featuring Rugosa (extinct order of solitary and colony corals)

Pink Opal

Hydrated silicon dioxide (SiO2·nH2O) with inclusions

Limonite (Yellow Ochre)

Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)

Chert (or Flint)

Chert (Sedimentary Cryptocrystalline Sio2)

Petrified Wood

Silicified Wood (SiO2)

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

Moss Agate

Silicon Dioxide (SiO2) with Chlorite/Oxide inclusions

Shale (with minor calcite veining)

Clastic sedimentary rock (primarily clay minerals and quartz)

Limestone

CaCO3 (Mainly Calcite or Aragonite)

Septarian Nodule

Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)

Jasper

Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline quartz (SiO2)

Banded Chert

Microcrystalline Quartz (SiO2)

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Aragonite

Aragonite (Calcium Carbonate - CaCO3)

Chert (and Limestone)

Silicon Dioxide (SiO2)

Green Jasper

Silicon Dioxide (SiO2)

Chert (specifically as a lithic artifact/projectile point)

Chert (Silicon dioxide, SiO2)

Chert (often called Jasper or River Siltstone)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Chalcedony)

Microcrystalline Quartz (SiO2)

Pink Opal

Hydrated Silica (SiO2·nH2O)

Fossilized Shark Tooth

Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Dinosaur Fossil (Skull)

Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)

Chert (variant Flint/Novaculite)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2) with iron oxide impurities

Chert (specifically Pink/Tan Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Brown variety)

Silicon Dioxide (SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Quartz Variety)

Silicon Dioxide (SiO2)