Igneous Or Sedimentary

Hematite

Iron(III) oxide (Fe2O3)

Pyrite

Iron Disulfide (FeS2)

Clear Quartz

Silicon Dioxide (SiO2)

Chalcedony (Agate/Blue Quartzite)

Silicon Dioxide (SiO2)

Garnet-Bearing Gneiss

Almandine-Garnet Gneiss

Chalcedony

Cryptocrystalline Quartz (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

River Stone (likely Siltstone or fine-grained Basalt)

Clastic Sedimentary (Siltstone) or Mafic Igneous (Basalt)

Granite (Dioritic or Hornblende-rich)

Phaneritic Plutonic Felsic to Intermediate Igneous Rock

Milky Quartz (Druzy Geode fragment)

Silicon Dioxide (SiO2)

Black Sand (Magnetite Sand)

Magnetite-rich Placers (Fe3O4)

Leopard Skin Jasper

Rhyolite (Silicon Dioxide with impurities), SiO2

Granite

Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase Feldspar)

Green Moss Agate / Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron and Manganese inclusions

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (in a rock matrix)

Quartz (SiO2)

Wonderstone (Banded Rhyolite)

Rhyolite (Silicon Dioxide with Iron Oxide impurities)

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Iron Oxide inclusions (Fe2O3)

Quartz (Milky or Druzy Quartz)

Silicon Dioxide (SiO2)

Hematite (Iron Ore)

Hematite (Fe2O3)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Granitic Gneiss

Gneiss (Metamorphic Rock)

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Clear Quartz

Silicon Dioxide (SiO2)

Gneiss

Gneiss

White Agate (Chalcedony)

Agate (Silicon Dioxide - SiO2)

Gneiss

Gneiss

Fluorite

Calcium Fluoride (CaF2)

Banded Agate (Pink Chalcedony)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

White Quartz Pebbles

Quartz (Silicon Dioxide, SiO2)

Quartz (Clear/White)

Silicon Dioxide (SiO2)

Fluorite (Blue)

Calcium Fluoride (CaF2)

Carnelian Agate

Carnelian (SiO2 with iron oxide impurities)

Blue Calcite

Calcium Carbonate (CaCO3)

Pyrite

Iron Sulfide (FeS2)

Amethyst with Marcasite accents

Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)

Hematite (Tumbled)

Iron(III) oxide (Fe2O3)

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Green Moss Agate

Silicon Dioxide with inclusions (SiO2 + Mn/Fe)

Arkosic Sandstone (or Conglomeritic Sandstone fragment)

Arkose (rich in feldspar)