Sedimentary (Chemical)

Chert (White-Tan variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (varietal: Jasper or Flint)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (Field Stone/Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Druzy Quartz on Host Rock

Silicon Dioxide (SiO2) with various iron-oxide inclusions

Chert (specifically Jasper or Flint variant)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Mudstone)

Silicon Dioxide (SiO2)

Chert / Flint

Cryptocrystalline Quartz (SiO2)

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Tan/Buff Chert)

Microcrystalline Quartz (SiO2)

Chert (often colloquially referred to as Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Chert / Flint

Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Ironstone (Limonitic Sandstone)

Ferruginous Sandstone (rich in Limonite: FeO(OH)·nH2O)

Chert Pebble (with Quartz Vein)

Chert (Cryptocrystalline Silica - SiO2)

Chert (Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Banded Chert

Microcrystalline Quartz (SiO2)

Chert (specifically Yellow Jasper variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (variations include Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Smooth River Pebble)

Silicon Dioxide (SiO2)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (specifically River Stone / Jasper variety)

Microcrystalline Quartz (SiO2)

Iron Gossan (Limonite/Goethite)

Hydrated Iron Oxides (FeO(OH)·nH2O) from oxidation zones

Chert (Banded Variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limestone

Calcareous Sedimentary Rock (CaCO3)

Limestone

Calcareous sedimentary rock (CaCO3)

Conglomerate

Conglomerate (clastic sedimentary rock)

Chert (Chert Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Limestone (Brecciated/Recrystallized)

Calcium Carbonate (CaCO3)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Chert / Chalcedony

Silicon Dioxide (SiO2)

Quartz (Raw Chunk)

Silicon Dioxide (SiO2)

African Turquoise

African Turquoise (a trade name for Jasper, a variety of Chalcedony: SiO2)

Chert (variously Flint or Jasper gravel)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Septarian Nodules / Weathered Silex)

Microcrystalline Quartz (SiO2)

Chert (Flint variety)

Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2

Bauxite

Bauxite (Mixture of Hydrous Aluminum Oxides)

Coquina or Fossiliferous Limestone

Fossiliferous Calcarenite (CaCO3)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Limestone

Calcium Carbonate (CaCO3)

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)