Gemstone

Obsidian

Amorphous volcanic glass (70-75% SiO2)

Rhodonite

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

Sodalite

Sodalite, Na8(Al6Si6O24)Cl2

Amber

Succinite (specifically for Baltic amber); Chemical formula approximately C10H16O

Blue Calcite

Calcium Carbonate (CaCO3)

Jasper

Jasper (Silicate mineral, SiO2)

Labradorite

Labradorite (Ca, Na)(Al, Si)4O8

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Corundum (Sapphire variant)

Aluminium oxide (Al2O3)

Serpentinite (often containing Jadeite/Nephrite)

Antigorite-rich Serpentine Rock, (Mg, Fe)3Si2O5(OH)4

Quartz (specifically Milky/White Quartz)

Silicon Dioxide (SiO2)

Chert (often referred to as Flint or Jasper when pigmented)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

Obsidian

Volcanic Glass (SiO2)

Carnelian (a variety of Chalcedony)

Silicon Dioxide (SiO2) with iron oxide impurities

Amethyst

SiO2 (Silicon Dioxide)

Aquamarine

Beryllium aluminum silicate (Be3Al2Si6O18)

Green Aventurine

Aventurine Quartz (SiO2 + Fuchsite mica)

Red Jasper (Quartz)

Silicon Dioxide (SiO2) with Iron impurities

Aquamarine

Beryl (Be3Al2Si6O18)

Jadeite Jade

Jadeite (NaAlSi2O6)

Prasiolite

Silicon Dioxide (SiO2)

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)3Si3O10(OH)2)

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Smoky Quartz

Silicon Dioxide (SiO2)

Kyanite (Purple variety)

Kyanite (Al₂SiO₅)

Epidote

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Citrine Quartz

Silicon Dioxide (SiO2) - Ferric Iron impurities

Dumortierite Quartz

Al7(BO3)(SiO4)3O3

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Larimar

Pectolite (Sodium Calcium Silicate Hydroxide) - (NaCa2(Si3O8)(OH))

Yellow Quartz (Rough)

Silicon Dioxide (SiO2)

Blue Topaz

Topaz [Al2SiO4(F,OH)2]

Green Aventurine

Aventurine (Silicon Dioxide with Fuchsite inclusions - SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Yellow Quartz (Citrine or Quartz Crystal with Iron Inclusions)

Silicon Dioxide (SiO2)

Pink Tourmaline (Rubellite)

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

Amethyst

Amethyst (Silicon Dioxide - SiO2 with Iron impurities)

Aquamarine

Beryl (Be3Al2Si6O18)