Organic Gem Material (Botanical)

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2)

Ferruginous Quartz Cobble

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Sandstone (likely Quartz Sandstone)

Arenite (SiO2 based)

Sandstone

Arenite (SiO2 based with primary clasts 0.0625 to 2 mm)

Siltstone with iron staining

Siltstone (primarily SiO2 with FeO(OH) coatings)

River Quartzite (River Rock)

Quartzite (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Ferruginous)

Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)

Banded Iron Formation (BIF)

Magnetite-Hematite Chert (Banded Iron Formation)

Gold

Native Gold (Au)

Sandstone

Arenite (primarily SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Coquina

Biogenic Limestone (Calcite/Aragonite base, CaCO3)

Tree Agate

Silicon Dioxide (SiO2) with inclusions of manganese and iron oxides

Green Fuchsite in Quartz (sometimes called Green Aventurine)

Fuchsite (Chrome-rich Muscovite) K(Al,Cr)2(AlSi3O10)(OH)2 in Quartz SiO2

Sandstone

Arenite (variable SiO2 composition)

Chert (Jasper/Quartzite river pebble)

Microcrystalline Silica (SiO2)

Sandstone

Arenite (composed primarily of SiO2)

US Penny

Cuprum (Copper: Cu) and Zincum (Zinc: Zn) Alloy

Granite Gneiss

Gneiss (high-grade metamorphic rock)

Sandstone

Arenite (SiO2 based)

Honey Calcite

Calcium Carbonate (CaCO3)

Red Sandstone

Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)

Red Sandstone

Arenite (Ferruginous Sandstone)

Red Sandstone

Arenite (Ferruginous Sandstone)

Aventurine (Green)

Aventurine Quartz (SiO2 + Fuchsite inclusions)

Chrysocolla in Jasper (Chryso-Jasper)

Cu2-xAlx(H2-xSi2O5)(OH)4·n H2O (Chrysocolla) + SiO2 (Jasper)

Sandstone

Arenite (primarily SiO2)

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Mica Schist

Mica Schist (primarily composed of Muscovite, Biotite, and Quartz)

Quartz Pebble (Water-worn)

Silicon Dioxide (SiO2)

Quartz Conglomerate

Quartz Conglomerate (clastic sedimentary rock)

Granite

Phaneritic Acidic Igneous Rock (Granite)

Quartzite Pebble

Quartzite (SiO2)

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 based)

Pink Granite

Phaneritic Felsic Igneous Rock (composed of orthoclase, quartz, and plagioclase)

Sandstone (Quartzose Sandstone)

Clastic sedimentary rock (primarily SiO2)

Siltstone

Siltstone (primarily composed of SiO2, Al2O3, and phyllosilicates)

Fossiliferous Limestone (Coquina / Shell Limestone)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Quartzite Pebble (with iron staining)

Quartzite (SiO2 with ferric oxide impurities)

Quartzite River Rock

Quartzite (primarily SiO2)

Reddish Brown Claystone or Siltstone

Argillite / Siltstone / Claystone