Mineral (Processed Alloy)

Rhodonite

Rhodonite (Manganese silicate, (Mn,Fe,Mg,Ca)SiO3)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Titanium Aura Quartz

Titanium bonded Silicon Dioxide (SiO2 + Ti)

Carnelian Agate

Silicon Dioxide (SiO2) - Chalcedony containing Iron Oxide impurities

Picture Jasper

Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions (SiO2)

Mahogany Obsidian

Volcanic glass (SiO2 with Hematite or Magnetite inclusions)

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood

Silicified Wood (SiO2)

Porphyritic Basalt (with Quartz or Calcite inclusion)

Porphyritic Basalt (Matrix: SiO2/MgO/FeO, Phenocryst: likely Quartz or Calcite)

Jasper with Quartz Druzy

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Sandstone (SiO2 with iron oxide inclusions)

Quartz Geode in Chert/Limestone Matrix

Silicon Dioxide (SiO2) within Sedimentary Host Rock

Red Jasper

Silicon Dioxide (SiO2) with impure Iron oxides

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Serpentine

Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4

Quartzite

Quartzite (primarily SiO2)

Gold Nugget

Native Gold (Au)

Milky Quartz with Country Rock contact

Silicon Dioxide (SiO2) in contact with Metamorphic/Igneous rock

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

Charoite

Charoite (Hydrated potassium, sodium, calcium, barium, strontium silicate hydroxide fluoride)

Bauxite (Pisolitic Bauxite)

Bauxite (mixture of Hydrous Aluminum Oxides)

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz (Water-Worn Pebble)

Silicon Dioxide (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2)

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Blue Quartzite

Quartzite with inclusions (often Dumortierite or Magnesio-riebeckite), SiO2

Jasper with Iron Staining

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

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions), SiO2 + Fe2O3

Petrified Wood

Silicified wood (Quartz variant, SiO2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Schist

Mica Schist (primarily Muscovite and Quartz)

Blue Tiger's Eye (Hawk's Eye)

Silicified Crocidolite (Pseudomorph of Quartz after Crocidolite), SiO2

Tiger's Eye

Pseudomorph of quartz after crocidolite (SiO2 with iron inclusions)

Mica Schist

Mica Schist (primarily Muscovite and Biotite phyllosilicates)

Chert (Septarian or Nodular variety)

Microcrystalline Quartz (SiO2)

Sedimentary rock with quartz veining

Laminated siltstone or mudstone with hydrothermal quartz veins

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz (with potential inclusion of feldspar)

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)