Sedimentary And Igneous

Magnetite (Iron Ore)

Magnetite (Fe3O4)

Mixed river stones; foreground likely sandstone

Quartz-rich sandstone, with associated rounded quartzite/chert and other cobbles

Dalmation Stone

Peralkaline Rock (mixed silicate minerals)

Dalmation Stone (often called Dalmatian Jasper)

Peralkaline Rock (Microgranite/Aplite), SiO2 with inclusions of Arfvedsonite

Magnetite (Iron Ore)

Magnetite (Fe3O4)

Clear Quartz

Silicon dioxide (SiO2)

Magnetite (potentially Hematite-rich)

Magnetite (Fe3O4)

Magnetite Orthorthotropic Rock

Magnetite (Fe3O4)

Dalmatian Stone

Peralkaline rhyolite

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (chalcedony variety), SiO2

Agate

Silicon Dioxide (Chalcedony), SiO2

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon dioxide (SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Quartz

Silicon Dioxide (SiO2)

Hematite

Hematite (Fe2O3)

Quartz

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Varieties including Rose Quartz and Citrine)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Apatite

Calcium phosphate fluorapatite, Ca5(PO4)3(F,Cl,OH)

Agate

Silicon dioxide (chalcedony), SiO2

Agate

Silicon Dioxide (Chalcedony), SiO2

Quartz

Silicon Dioxide (SiO2)

White Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

White Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Amethyst Cluster

Silicon dioxide (Quartz variety, $SiO_2$)

Quartz

Silicon Dioxide (SiO2)

Agate

Silicon dioxide (Chalcedony), SiO2