Organic Gemstone (Not A Rock Or Mineral)

Milky Quartz

Silicon Dioxide (SiO2)

Amber (Copal)

Organic gemstone, fossilized tree resin (often immature amber or copal)

Turquoise

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

Quartz (Milky/Clear Quartz)

Silicon Dioxide (SiO2)

Coal (Bituminous or Anthracite)

Carbonaceous sedimentary rock (primarily Carbon, C)

Turquoise

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

Nephrite Jade

Nephrite

Petrified Wood

Silicified Wood (primarily SiO2)

Prehnite on Basalt

Prehnite - Ca2Al(AlSi3O10)(OH)2

Chert (with Lichen)

Microcrystalline Quartz (SiO2)

Serpentine (variety: Serpentine Rock)

Antigorite, Lizardite, or Chrysotile; formula generally (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Granitic Pegmatite

Pegmatitic Granite

Jasper (likely Brecciated or Multi-colored)

Jasper (SiO2)

Turquoise

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

Azurite and Malachite on Matrix

Cu3(CO3)2(OH)2 (Azurite) and Cu2CO3(OH)2 (Malachite)

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

Amber

Succinite

Clear Quartz Sphere

Quartz (Silicon Dioxide, SiO2)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Blue Chalcedony

Chalcedony (SiO2)

Sparkling Druzy Quartz on Matrix

Silicon Dioxide (SiO2) with iron oxide inclusions

Shell Cameo (Sardonyx Shell)

Cassis madagascariensis (Sardonyx shell)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Chert (White Flint)

Silicon Dioxide (SiO2)

Pyrite

Pyrite (Iron Disulfide), FeS2

Chert (specifically Jasper/Brown Chert)

Silicon Dioxide (SiO2)

Fossiliferous Limestone (Coquina)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Black Jasper (Black Onyx substitute)

Silicon Dioxide (SiO2) with carbonaceous impurities

Clear Quartz (Druzy/Crystal Cluster)

Silicon Dioxide (SiO2)

Emerald in Host Rock

Beryl (Be3Al2Si6O18) containing Chromium and/or Vanadium

Peridot

Olivine ((Mg, Fe)2SiO4)

Dalmation Stone

Peralkaline Rock (mixed silicate minerals)

Kimberlite

Kimberlite

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Quartz with Iron Oxide Monzonite or Sandstone contact

Quartz (SiO2) with Limonite/Hematite staining

Chert (Smooth River Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Amber

Succinite (specifically for Baltic amber); Approximate formula: C10H16O

Clear Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz with Iron Staining

Silicon Dioxide (SiO2)

Quartz Pebble (Milky Quartz)

Silicon Dioxide (SiO2)