Organic Mineraloid

Fancy Jasper (Agate/Chert mix)

Silicon Dioxide (SiO2) with impurities

Red Jasper

Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Crinoid Stem Fragment

Crinoid (Phylum Echinodermata, Class Crinoidea)

Chert (Flint)

Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)

Chert (specifically Blue or Grey Chert/Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (and/or Flint)

Chert (Cryptocrystalline variety of Quartz, SiO2)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fossilized Bone Fragment

Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)

Jasper

Jasper (Cryptocrystalline variety of Quartz, SiO2)

Chert (often called Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Flint or Common Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (variations include Flint/Novaculite)

Chert (formula: SiO2)

Chert (Jasper/Agate variety)

Silicon Dioxide (SiO2)

Chert (varietal: Flint or River Pebble)

Silicon Dioxide (SiO₂)

Jasper

Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (and/or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Chert (White Chert)

Silicon Dioxide (SiO2)

Orthoceras Fossil Limestone

Orthoceras sp. (Calcium Carbonate, CaCO3)

Chert (specifically Flint or Jasper variant)

Cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (often called Flint or River Rock)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Chert

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

Petrified Wood

Silicified wood (principally SiO2)

Chert / Jasper / Agate (Chalcedony Group)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint Pebble)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)

Fossil Shark Tooth (Otodus obliquus)

Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))

Red Chert (Jasper)

Chert / Microcrystalline Quartz (SiO2)

Chert (Nodule)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (primarily SiO2)

Dendritic Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions

Chert (Chert Nodule with Cortex)

Microcrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods) in Carboniferous or Devonian Limestone