Sedimentary Or Mineral

Satin Spar Selenite

Gypsum (CaSO4·2H2O)

Yellow Ochre (Limonite)

Limonite (FeO(OH)·nH2O)

Quartz Crystal Cluster

Silicon Dioxide (SiO2)

Pyrite

Iron Disulfide (FeS2)

Galena

Lead sulfide (PbS)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Rainbow Fluorite

Fluorite (Calcium Fluoride, CaF2)

Tumbled clear quartz

Quartz (SiO₂)

Tumbled clear quartz

Quartz (silicon dioxide, SiO₂)

Small quartz-rich mineral fragment

Quartz (SiO₂), possibly milky or chalcedonic quartz

Pyrite in Quartz Matrix

Iron Sulfide (FeS2) with Silicon Dioxide (SiO2)

Mica (Muscovite or Biotite)

Sheet silicate mineral group (e.g., KAl2(AlSi3O10)(F,OH)2)

Sandstone

Arenite

Orange Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Limonite Concretion

Hydrated iron oxide-hydroxide, FeO(OH)·nH2O

Red Sandstone

Quartzose Sandstone

Anhydrite

Calcium Sulfate (CaSO4)

Actinolite

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

K-Feldspar (Potassium Feldspar)

Orthoclase / Microcline (KAlSi3O8)

Quartz

Silicon Dioxide (SiO2)

Calcite

Calcium Carbonate (CaCO3)

Limonite or Goethite (Ironstone)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Kaolinite (China Clay)

Kaolinite (Al2Si2O5(OH)4)

Limonite

FeO(OH)•nH2O

Pyrite

Iron Sulfide (FeS2)

Limonite

FeO(OH)•nH2O

Pink Sandstone

Quartz arenite / Quartz sandstone (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Pyrite

Iron Sulfide (FeS2)

Celestine (Celestite)

Strontium sulfate (SrSO4)

Halite (Rock Salt)

Halite (Sodium Chloride, NaCl)

Sandstone (or Siltstone / Ceramic Sherd)

Arenite / Siltstone (dominated by SiO2)

Geode

Quartz nodule / Chalcedony-lined cavity

Jasper

Microcrystalline quartz (SiO2)

Red Calcite

Calcium Carbonate (CaCO3)

Quartz / Chalcedony Pebble

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)