Mineral (Processed Alloy)

Quartz Vein in River Siltstone

Crystalline Quartz (SiO2) in Siliclastic Matrix

Granite Sand (Decomposed Granite)

Grus / Quartz-Feldspar Detritus

Milky Quartz

Silicon Dioxide (SiO2)

Veined Quartz

SiO2 (Silicon Dioxide)

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Caribbean Calcite

Calcium Carbonate (CaCO3) with Aragonite (CaCO3)

Schist

Mica Schist (primarily composed of quartz, feldspar, and mica)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Tiger's Eye

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

Red Jasper

Jasper (Silicon Dioxide based crypto-crystalline Quartz with Iron inclusions)

Iron Gossan (Limonite/Goethite)

Hydrated Iron Oxides (FeO(OH)·nH2O) from oxidation zones

Blue Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of asbestiform silicates)

Fossiliferous Rock (likely Dinosaur Fossil in Matrix)

Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)

Bauxite

Al2O3·2H2O (principally composed of gibbsite, boehmite, and diaspore)

Tourmalinated Quartz

Quartz (SiO2) with Schorl (NaFe3Al6(BO3)3Si6O18(OH)4) inclusions

Blue Calcite

Calcium Carbonate (CaCO3)

Rhodonite

(Mn,Fe,Mg,Ca)SiO3

Rhodonite

Manganese Inosilicate (Mn,Fe,Mg,Ca)SiO3

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Paraiba Tourmaline

Elbaite Tourmaline (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) - Copper-bearing

Quartz Druzy Geode

Silicon Dioxide (SiO2) - Crystalline Variety

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Quartz crystal with Pyrite inclusions

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Orange Calcite

Calcium Carbonate (CaCO3)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Travertine (Ceramic Tile)

Terrestrial Sedimentary Rock / Calcium Carbonate (CaCO3)

Red Jasper

Jasper (Silicate mineral - SiO2)

Sparkling Druzy Quartz on Matrix

Silicon Dioxide (SiO2) with iron oxide inclusions

Sandstone (Ferruginous)

Arenite with Iron Oxide cement

Lapis Lazuli

Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])

Porphyry (Flower Stone)

Porphyry (Andesite or Basalt matrix)

Petrified Wood

Silicified Wood (primarily Chalcedony/Quartz, SiO2)

Red Jasper

Silicon Dioxide with Iron inclusions (SiO2)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Titanium Coated Kyanite (Aura Kyanite)

Aluminosilicate (Al2SiO5) with a Titanium-Niobium vacuum-deposited coating

Desert Varnish on Sandstone

Ferromanganese coating on Quartz Arenite

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

Aquamarine

Beryl (Be3Al2Si6O18)

Druzy Quartz on Limestone

Silicon Dioxide (SiO2)