Limestone

Fossiliferous Limestone (Coquina / Shell Limestone)

CaCO3 (Calcium Carbonate)

Limestone (specifically Crushed Limestone/Calcictic)

Calcium Carbonate (CaCO3)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Flint)

Silicon dioxide (SiO2)

Chert

Chert (microcrystalline quartz)

White Marble

Recrystallized Calcite (CaCO3)

Marble

Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)

Vesuvianite (Idocrase)

Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10

Blue Apatite

Fluoroapatite (Ca5(PO4)3F)

Chert (Flint variety)

Microcrystalline Quartz (SiO2)

Flint (within Limestone matrix)

Silicon dioxide (SiO2)

Fossilized Favosites (Honeycomb Coral)

Favosites (extinct genus of tabulate coral)

Chert (Field-collected Arrowhead-shaped Fragment)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (with Limonite staining)

Microcrystalline Quartz (SiO2)

Chert (Jasper variation)

Microcrystalline Quartz (SiO2)

Chert (often called Jasper in this color)

Microcrystalline quartz (SiO2)

Chert (Flint)

Microcrystalline silica (SiO2)

Chert (Jasper/Flint variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Chert Breccia

Brecciated Chert (Microcrystalline Silica)

Quartz Geode (Cracked Open)

Quartz (Silicon Dioxide - SiO2)

Chert (specifically Flint or Common Chert)

Silicon Dioxide (SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Chert (variant Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz Druzy on Geode Fragment

Silicon Dioxide (SiO2)

Fossilized Brachiopod

Brachiopoda (Class Rhynchonellata or Spiriferida)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Arrowhead/Tool variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Fossiliferous)

Silicon Dioxide (SiO2)

Fossilized Coral (Petoskey Stone or Rugose Coral)

Antophyllum (Hexagonaria) or Scleractinia (CaCO3)

Geode (unopened)

SiO2 - Chert-shelled concretion (mostly Quartz)

Chert (Quartz Variety)

Chert (SiO2)

Chert / Flint

Microcrystalline Quartz (SiO2)

Chert (specifically Flint or Common Opal variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert Nodules (with Gryphaea or Shell inclusions)

Microcrystalline Quartz (SiO2) with Calcitic inclusions

Chert (with possible fossils)

Microcrystalline quartz (SiO2)

Chert Arrowhead

Microcrystalline Quartz (SiO2)

Chert (Flint)

Chert (SiO2)

Chert (often called Jasper or Flint in this color variety)

Silicon Dioxide (SiO2)

Chert (Mudstone)

Microcrystalline Quartz (SiO2)

Chert (Flint variety)

Microcrystalline Quartz (SiO2)

Fossilized Turritella Gastropod (Internal Mold)

Turritella (Fossil Gastropod Crust)