Mineral (Silicate Replaced Organic Material)

Diorite

Intrusive Igneous Diorite (intermediate composition)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limonite-stained Chert

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Asphalt

Asphalt concrete (engineered material, not a naturally occurring rock/mineral in this form)

Limonite (often after Hematite or Goethite)

Limonite (FeO(OH)·nH2O)

Chert (variations include Flint/Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper/River Stone)

Silicon dioxide (SiO2) - Microcrystalline quartz

Olivine (in Peridotite/Dunite form)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Glauconitic Sandstone (Greensand pebble)

Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Tufa

Calcareous Tufa (Calcium Carbonate, CaCO3)

Fossil Coral

Scleractinia (Anthos), primarily Calcium Carbonate (CaCO3)

Chert (often called Flint or Jasper)

Silicon Dioxide (SiO2)

Epidote in Quartz

Quartz with Epidote inclusions (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH) inclusions)

Slate

Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)

Chert (specifically Red Chert / Jasper nodule)

Silicon dioxide (SiO2)

Chert (Chalcedony/Flint)

Silicon Dioxide (SiO2)

Flint

Chert (Silicon dioxide, SiO2)

Red Jasper

Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Jasper (Green/Yellow Moss Jasper)

Silicon Dioxide (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Unakite

Epidote-Feldspar rock

Travertine (Tufa)

Calcium Carbonate (CaCO3)

Chert (Flint)

Chert (SiO2)

Chert (Pink/Red variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Amber

Succinite

Mystic Topaz

Aluminum silicate fluoride hydroxide with titanium coating (Al2SiO4(F,OH)2)

Orange Quartz (or Tumbled Carnelian)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (and Jasper/Flint variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert / Flint

Silicon Dioxide (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Iron-Stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (Flint)

Chert (SiO2)

Chert (Flint variety)

Chert (Cryptocrystalline Quartz, SiO2)