Limestone

Green Fluorite (Fluorite Sphere)

Calcium Fluoride (CaF2)

Chert (Green variety)

Cryptocrystalline Quartz (SiO2)

Chalcedony (Pink/Gray variety)

Silicon Dioxide (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Chert (River Pebble)

Silicon Dioxide (SiO2)

Chalcedony (Botryoidal or Geode form)

Silicon Dioxide (SiO2)

Celestite (Celestine)

Strontium Sulfate (SrSO4)

Black Spinel

Magnesium Aluminum Oxide (MgAl2O4)

Chert (specifically Flint or Common Chert)

Microcrystalline Quartz (SiO2)

Spondylus Oyster Calcification / Fossilized Oyster

Spondylus (Thorny Oyster) / Calcium Carbonate (CaCO3)

Rough Emerald (Beryl)

Emerald (Be3Al2(SiO3)6 with Cr/V impurities)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (Gravel)

Microcrystalline Quartz (SiO2)

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Iridescent Ammonite

Ammonoidea (Species: likely Cleoniceras or Desmoceras); Mineral: Aragonite/Ammolite (CaCO3)

Connemara Marble

Ophiocalcite (Serpentinitic Marble)

Lapis Lazuli

Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Oolitic Chert

Oolitic Microcrystalline Quartz (SiO2)

Chert (Gravel)

Chert (Cryptocrystalline silicon dioxide, SiO2)

Chert (specifically Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chalk (Limestone variant)

Calcium Carbonate (CaCO3)

Orthoceras Fossil Limestone

Orthoceras (extinct Cephalopod fossil) in Matrix

Orthoceras fossil in limestone

Orthoceras (extinct genus of cephalopod)

Fossilized Shell in Limestone

Bivalve fossil (CaCO3) in Carbonate Sedimentary Rock

Limestone with Calcite Veins

Calcium Carbonate (CaCO3)

Coquina or Fossiliferous Limestone

Fossiliferous Calcarenite (CaCO3)

Coquina / Fossiliferous Limestone

Calcite-rich Bioclastic Sedimentary Rock (CaCO3)

Coquina / Fossiliferous Limestone

Calcareous bioclastic sedimentary rock (CaCO3)

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Optical Calcite

Calcium Carbonate (CaCO3)

Fluorite

Calcium Fluoride (CaF2)

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Nephrite Jade

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2)

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Lapis Lazuli (Simulated)

Lapis Lazuli (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2

Nephrite Jade

Ca2(Mg, Fe)5Si8O22(OH)2

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Nephrite Jade

Nephrite (a variety of the Calcium magnesium iron silicate mineral series Actinolite), Ca2(Mg, Fe)5Si8O22(OH)2

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Chert (Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (Yellow/Brown Jasper)

Silicon Dioxide (SiO2)

Chert / Flint Nodule

Microcrystalline or Cryptocrystalline Quartz (SiO2)