Synthetic Polymer (Polylactic Acid)

Red Shale

Fissile Siliciclastic Sedimentary Rock

Quartzite

Quartzite (SiO2)

Basalt with Calcite Veins

Basalt (containing CaCO3 inclusions)

Quartzite Pebble

Quartzite (primarily SiO2)

Quartzite

Quartzite (SiO2)

Quartzite Pebbles

Quartzite (SiO2)

Azurite in Gossan

Azurite (Cu3(CO3)2(OH)2) in Limonite/Goethite matrix

Quartzite

Quartzite (SiO2)

Coquina Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Diamond

Diamond (pure carbon; C)

Shale with Vein Infillings

Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.

Rhodochrosite

Manganese Carbonate (MnCO3)

Quartzite

Quartzite (primarily SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Limestone with Calcite Veining

Calcium Carbonate (CaCO3)

Green Quartzite (Aventurine variety)

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Picasso Stone

Metamorphosed Calcium Carbonate (Limestone)

Marble

Recrystallized Carbonate Rock (CaCO3)

Quartzite

Quartzite (primarily SiO2)

Tufa

Calcareous Tufa (CaCO3)

Quartzite

Quartzite (chiefly SiO2)

Malachite

Copper carbonate hydroxide, Cu2CO3(OH)2

Chalk (Calcitic)

Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock

Limestone

Calcium Carbonate (CaCO3)

Rhodochrosite

Manganese carbonate (MnCO3)

Oolitic Limestone

Oolitic Limestone (CaCO3)

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Quartzite

Quartzite (composed primarily of Silica, SiO2)

Fossiliferous Limestone (with Coralline Inclusions)

Calcium Carbonate (CaCO3)

Shale with Plant Fossils / Carbonaceous Shale

Laminated Mudrock (Siliciclastic)

Pink Granite (Alkali Feldspar Granite)

Phaneritic Felsic Igneous Rock (composed primarily of KAlSi3O8, SiO2, and NaAlSi3O8)

Quartzite Pebble

Quartzite (predominantly Silicon Dioxide - SiO2)

Celestine (or Celestite) on Matrix

Celestine (SrSO4)

Red Sandstone

Arenite (composed primarily of SiO2 with Fe2O3 cementation)

Limestone

Calcium Carbonate (CaCO3)

Yellow Calcite

Calcium Carbonate (CaCO3)

Coquina

Biogenic Limestone (Calcium Carbonate, CaCO3)

Quartzite

Quartzite (primarily SiO2)

Basalt (River or Beach Pebble)

Basalt (Mafic Extrusive Igneous Rock)

Quartzite (River Pebble)

Meta-quartzite (composed primarily of SiO2)

Marble

Recrystallized Calcite (CaCO3)

Greenstone (Metabaltic/Greenschist)

Chlorite schist / Meta-basalt