Limestone

Chert Pebble

Microcrystalline Quartz (SiO2)

Ruby

Corundum (Al2O3 with Chromium traces)

Optical Calcite

Calcium Carbonate (CaCO3)

Lapis Lazuli (blue bead) and Moss Agate (green heart)

Lapis Lazuli (lazurite-based rock) and Moss Agate (SiO2 with manganese/iron inclusions)

Celestite (Celestine)

Strontium sulfate (SrSO4)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Blue Apatite

Apatite, Ca5(PO4)3(F,Cl,OH)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pyrite in Matrix (Fool's Gold)

Iron Disulfide (FeS2)

Epidote

Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Orange Calcite

Calcium Carbonate (CaCO3)

Chalcedony (Agate/Chert variety)

Silicon Dioxide (SiO2)

Celestite (Celestine)

Strontium sulfate (SrSO4)

Sand Dollar Fossil

Echinoidea (Clypeasteroida)

Blue Calcite

Calcium Carbonate (CaCO3)

Chert (Novaculite Variety)

Microcrystalline Quartz (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Quartz Pebble (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Ruby (set in a gold pendant)

Ruby (Variety of Corundum, Al2O3)

Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Marble

Recrystallized Calcite / Dolomite (CaCO3)

Chert (River Pebble)

Microcrystalline Quartz (SiO2)

Calcite with iron staining

Calcium Carbonate (CaCO3)

Chert (River Pebble)

Microcrystalline quartz (SiO2)

Chert (and Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Fluorite, Turquoise, and Calcite set

Calcium Fluoride (CaF2), Hydrous Phosphate of Copper and Aluminum (CuAl6(PO4)4(OH)8·4H2O), Calcium Carbonate (CaCO3)

Gastropod Steinkern (Internal Mold Fossil)

Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix

Quartzite

Quartzite (SiO2)

Piddock bored rock (likely Mudstone or Shale)

Ichnofossil (Gastrochaenolites borings) in Fine-grained Sedimentary Rock

Chert (potentially Flint or Mudstone)

Microcrystalline Quartz (SiO2)

Chert (containing Fossil Inclusions)

Microcrystalline Quartz (SiO2)

Calcite

Calcite (Calcium Carbonate, CaCO3)

Chert (Flint Nobule)

Silicon Dioxide (SiO2)

Chert (Agatized/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

White Marble

Recrystallized Calcite (CaCO3)

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Black Chert/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint)

Chert (SiO2)

Coarse-Grained Marble

Recrystallized Limestone (Major component: CaCO3)