Anthropogenic (Man Made Artifact)

Lepidolite (likely)

K(Li,Al)3(Al,Si)4O10(F,OH)2 (Phyllosilicate mineral, part of the mica group)

Sandstone (with manganese staining)

Clastic sedimentary rock (primarily SiO2)

Sandstone (Weathered Cobble)

Clastic Sedimentary Rock (primarily SiO2)

Limestone with Calcite Crystals

Calcium Carbonate (CaCO3)

Granite Cobble

Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Ferruginous Sandstone (Ironstone)

Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)

Blue Quartzite (Aventurine)

Quartzite (primarily SiO2) with inclusions of Dumortierite or Magnesio-riebeckite

Limestone

Calcium Carbonate (CaCO3)

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily SiO2 with Fe2O3 oxides)

Cinnabar in Quartz

Silicon Dioxide (SiO2) with Mercury Sulfide (HgS) inclusions

Aquamarine and clear quartz

Aquamarine (Be3Al2Si6O18), Quartz (SiO2)

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2)

Blue Sapphire (faceted in jewelry)

Corundum (Al2O3)

Yellow Quartzite Pebble

Quartzite (primarily Silicon Dioxide - SiO2)

Rainbow Fluorite

Fluorite (Calcium Fluoride, CaF2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Amazonite (or Amazon Stone)

Potassium Feldspar (Microcline), K(AlSi3O8)

Cockle Shell (Fossil or Recent)

Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)

Pyrite

Iron Disulfide (FeS2)

Limestone

Calcium Carbonate (CaCO3)

White Agate (Chalcedony)

Agate (Silicon Dioxide - SiO2)

Feldspar Rich Granite with Limonite Staining

K-Feldspar Granite (KAlSi3O8)

Sandstone

Arenite (primarily SiO2)

Limestone

Calcareous Sedimentary Rock (CaCO3)

Serpentine

Serpentinite (complex of Mg, Fe, Ni, Al, Zn, Mn)Si2O5(OH)4

Nephrite Jade

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

Kyanite

Kyanite (Al2SiO5)

Red Garnet

Almandine and Pyrope (Silicate minerals: Fe3Al2(SiO4)3 and Mg3Al2(SiO4)3)

Petrified Wood

Silicified wood (Quartz, SiO2)

Green Calcite

Calcium Carbonate (CaCO3)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Halite (Rock Salt)

Halite; NaCl (Sodium Chloride)

Clear Quartz (Rock Crystal)

Quartz (SiO₂)

Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)

Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.

Sandstone Clast

Arenite (primarily SiO2)

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Sandstone

Arenite (primarily SiO2 with iron oxide cementation)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of Titanium, Iron, or Manganese

Quartz

Quartz (SiO2 - Silicon Dioxide)

Snowflake Obsidian

Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)

Sandstone

Arenite (primarily SiO2)