Mineral Composite

Limonite

Limonite (Hydrous iron oxides, FeO(OH)·nH2O)

Quartz Vein in Host Rock (Gneiss/Schist)

Silicon Dioxide (SiO2) within a metamorphic matrix

Red Sandstone

Arenite (with Iron Oxide cement)

Sandstone with Iron Oxide (Limonite/Hematite)

Ferruginous Sandstone (SiO2 with FeO(OH)·nH2O)

Moonstone

Orthoclase (Potassium Feldspar) - (K,Na)AlSi3O8

Sandstone (Pebble)

Sandstone (arenite, arkose, wacke depending on composition)

Specular Hematite (Iron Ore)

Iron(III) oxide (Fe2O3)

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)

Sandstone

Clastic sedimentary rock (primarily SiO2)

Feldspar

KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8

Lepidolite with Quartz

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2

Quartz Vein in Schist

Quartz (SiO2) in Mica Schist

Grey River Stone (Gneiss/Schist mix)

Foliated Metamorphic Rock (variable mineral formula)

Granite Pebble (Salt and Pepper Granite)

Felsic Intrusive Igneous Rock (Granite)

Granite Gneiss

Gneiss (High-grade regional metamorphic rock)

Sandstone or Limestone

Arenite or Calcareous Sedimentary Rock

Basalt with Epidote (Flowerstone-like texture)

Amygdaloidal Basalt (silicate mineral inclusions)

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily Quartz, SiO2)

Sardonyx Agate Sphere

Cryptocrystalline Quartz (SiO2) with iron oxide inclusions

Turquoise (set in silver jewelry)

Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Azurite and Malachite on Matrix

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

Turquoise

Turquoise (Hydrated phosphate of copper and aluminium) CuAl6(PO4)4(OH)8·4H2O

Quartz with Arsenopyrite

Silicon Dioxide (SiO2) with Iron Arsenic Sulfide (FeAsS)

Chalcopyrite

Chalcopyrite (CuFeS2)

Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Siltstone with Weathering Rind

Siltstone (composed of microscopic quartz and clay minerals)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of Iron Oxide)

Hematite

Iron(III) oxide (Fe2O3)

Dalmatian Stone

Peralkaline rhyolite

Quartz (likely Rose Quartz or Milky Quartz based on color)

Quartz (SiO2 - Silicon Dioxide)

Blue Apatite

Fluoroapatite (Ca5(PO4)3F)

Tiger's Eye (with Blue Tiger's Eye / Hawk's Eye)

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)

Limonite (Iron Ore)

Limonite (Hydrous iron(III) oxide-hydroxide mixture, primarily FeO(OH)·nH2O)

Lepidolite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within a metamorphic matrix

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Fluorite (Green)

Calcium Fluoride (CaF2)

Ruby in Kyanite

Corundum in Disthene (Al2SiO5 + Al2O3)

Quartz Pebble

Silicon Dioxide (SiO2)

Yellow Ochre / Limonite

Limonite (FeO(OH)·nH2O)