Organic Gemstone (Not A Mineral)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Ametrine

Ametrine (SiO2 - Silicon Dioxide with varied iron impurities)

Agate Geode Slice (with Druzy Quartz)

Silicon Dioxide (SiO2)

Vesuvianite (Idocrase)

Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with impurities of Hematite or Goethite

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Green Quartz (Prasiolite variant or Aventurine)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Peridot (Olivine)

Olivine ((Mg, Fe)2SiO4)

Citrine or Yellow Quartz

Silicon Dioxide (SiO2) with iron impurities

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Tiger's Eye

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

Granite Pegmatite with Tourmaline and Muscovite

Pegmatite (Feldspar: KAlSi3O8, Quartz: SiO2, Schorl: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH))

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Turquoise

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

Citrine (Heat-treated Amethyst)

Silicon Dioxide (SiO2) with iron impurities

Quartz (Citrine or Smoky variant)

Silicon Dioxide (SiO2)

Quartz (Clear/White)

Silicon Dioxide (SiO2)

Oceanside Agate (Orbicular Agate)

Silicon Dioxide (SiO2) - Variety of Chalcedony

Chert (and/or Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Lapis Lazuli

Lapis lazuli (a rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Fluorite

Calcium Fluoride (CaF2)

Rhodonite

Rhodonite (Mn,Fe,Mg,Ca)SiO3

Precious Opal in Matrix

Hydrated Silica (SiO2·nH2O)

Chert (specifically Gray/Blue Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Turquoise (Rough)

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

Sodalite

Sodalite (Sodium Aluminum Silicate Chloride), Na8(Al6Si6O24)Cl2

Chert (with Quartz vein)

Chert (Silicon Dioxide, SiO2)

Chert (Iron-stained)

Chert (primarily Microcrystalline Quartz, SiO2)

Chert (Brecciated or Veined)

Silicon Dioxide (SiO2)

Olivine (Peridot)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Amazonite

K(AlSi3O8), Microcline (potassium feldspar)

Jasper

Jasper (Silicon Dioxide, SiO2)

Kyanite in Quartz

Kyanite (Al2SiO5) with Quartz (SiO2)

Cavansite

Cavansite (Ca(VO)Si4O10·4H2O)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Epidote in Quartz (Unakite-like specimen)

Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)) in Quartz (SiO2)

Mookaite Jasper

Radiolarite (Silicon Dioxide, SiO2)

Picture Jasper

Silicon Dioxide (SiO2) with iron oxide and mineral inclusions

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with Iron inclusions)

Precious Opal

Hydrated Silica (SiO2·nH2O)