Synthetic Polymer (Polylactic Acid)

Quartzite Pebble

Quartzite (primarily SiO2)

Pink Quartzite

Quartzite (SiO2 with iron oxide impurities)

Fossiliferous Limestone

Fossiliferous Limestone (CaCO3)

Marble

Recrystallized Calcite (CaCO3)

Quartzite

Quartzite (SiO2)

Limestone (specifically Iron-stained or Argillaceous Limestone)

Calcium Carbonate (CaCO3) with Iron Oxide (Fe2O3) impurities

Fossilized Shell in Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Limestone (with potential fossil inclusions)

Calcium Carbonate (CaCO3)

Turquoise (with Hematite)

CuAl6(PO4)4(OH)8·4H2O

Granite

Intrusive igneous rock (Acidic)

Coquina / Fossiliferous Limestone

Bioclastic Limestone (CaCO3)

Quartzite

Quartzite (predominantly SiO2)

Quartzite

Quartzite (primarily SiO2)

Sandstone

Arenite (SiO2 principal)

Quartzite (specifically a river-worn pebble)

Quartzite (primarily SiO2)

Malachite

Copper carbonate hydroxide Cu2CO3(OH)2

Limestone

Calcareous sedimentary rock (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Shale

Shale (Sedimentary rock composed of mud/clay minerals)

Quartzite Pebbler

Quartzite (SiO2)

Ferruginous Quartz

Iron-stained Quartz (Silicon Dioxide + Fe2O3 / FeO(OH))

Marble

Metamorphic rock composed of Recrystallized Carbonate Minerals (chiefly CaCO3)

Peacock Ore (Bornite or Chalcopyrite treated with acid)

Bornite (Cu5FeS4) or Acid-washed Chalcopyrite (CuFeS2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Aquamarine

Aquamarine (Beryl variety); Be3Al2Si6O18

Limestone

Calcium Carbonate (CaCO3)

Yellow Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Yellow Calcite

Calcium Carbonate (CaCO3)

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

White Marble

Metamorphosed Limestone (principally CaCO3)

Jade (likely Jadeite)

Jadeite (a pyroxene mineral) or Nephrite (a variety of amphibole mineral)

Marble (Calcitic)

Metamorphosed Limestone (CaCO3)

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Amethyst (Purple), Sulfur (Yellow), and Blue Apatite

SiO2 (Quartz), S (Native Sulfur), Ca5(PO4)3(F,Cl,OH) (Apatite Group)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Diamond (Rough)

Diamond (Carbon, C)

Ruby

Corundum (mineral species), variety: Ruby (Al2O3 with Cr3+ as the chromophore)