Organic Gemstone (Not A Mineral)

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

Opal

Hydrated amorphous silica (SiO2·nH2O)

Amethyst

Amethyst (Silicon Dioxide with iron impurities), SiO2

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Opal

Hydrated Silica (SiO2·nH2O)

Quartz

Silicon dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Garnet (likely Almandine)

Almandine (Fe3Al2(SiO4)3)

Dragon Stone (Dragon Blood Jasper)

Epidote with Pietersite or Red Jasper inclusions (varied SiO2 and Ca2(Al,Fe)3(SiO4)3(OH))

Chert (Jasper)

Microcrystalline Quartz (SiO2) with Iron Oxide impurities

Clear Quartz

Silicon Dioxide (SiO2)

Diamond in Kimberlite

Diamond in Kimberlite Matrix (Diamond: C, Kimberlite: complex Potassic Peridotite)

Apatite

Apatite group mineral (e.g., Fluorapatite - Ca5(PO4)3F, Chlorapatite - Ca5(PO4)3Cl, Hydroxylapatite - Ca5(PO4)3(OH))

Olivine (Peridotite)

(Mg,Fe)2SiO4 (Magnesium Iron Silicate)

Quartz

Silicon Dioxide (SiO2)

White Jade / Jadeite

NaAlSi2O6 (Sodium Aluminum Silicate)

Anyolite (Ruby in Zoisite)

Zoisite with inclusions of Corundum; Ca2Al3(SiO4)3(OH) + Al2O3

Pegmatite (Granite Pegmatite)

Intrusive Igneous Rock (Granite Pegmatite)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Clear Quartz Fragment

Quartz (Silicon Dioxide, SiO2)

Epidote (Unakite-related)

Epidote (Ca2(Al,Fe)3(SiO4)3(OH))

Amethyst

Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities

Citrine Geode (or Druzy Citrine)

Silicon Dioxide (SiO₂) - a variety of Quartz

Epidote

Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

Quartz (Iron-stained)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Agate (or Chalcedony)

SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz

Pyrite

Pyrite (Iron Disulfide), FeS2

Yellow Jasper

Jasper (Silicon Dioxide, SiO2 plus various mineral impurities)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Diamond

Diamond (C)

Corundum (Sapphire/Ruby in Matrix)

Corundum (Al2O3)

Silicon Carbide (Carborundum)

Silicon Carbide (SiC) / Moissanite (natural)

Wood Jasper

Siliceous sedimentary rock (variety of Chert/Chalcedony)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Diamond (in Matrix)

Carbon (C)

Smoky Quartz

Silicon Dioxide (SiO2)

White Quartz

Silicon Dioxide (SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Satin Spar (Gypsum)

Calcium Sulfate Dihydrate (CaSO4·2H2O)

Quartz (Milky or Smoky variety)

Silicon Dioxide (SiO2)

Raw Diamond (Rough Uncut)

Diamond (C - pure carbon)