Industrial Byproduct

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Schorl (Black Tourmaline) in Quartz Matrix

Schorl: NaFe3Al6(BO3)3Si6O18(OH)4 (Complex Borosilicate)

Chert with Druzy Quartz Geode

Microcrystalline Quartz (SiO2)

Corundum (variety Ruby/Sapphire)

Aluminum Oxide (Al2O3)

White Topaz

Aluminum silicate fluoride hydroxide (Al2SiO4(F,OH)2)

Red Garnet

Pyrope-Almandine series (Mg3Al2(SiO4)3 to Fe3Al2(SiO4)3)

Dyed Magnesite (often sold as Red Turquoise or Howlite)

Magnesium Carbonate (MgCO3)

Blue Sapphire (faceted in jewelry)

Corundum (Al2O3)

Black Tourmaline in Quartz and Feldspar Matrix

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4) with Quartz and Feldspar

White Quartzite

Quartzite (primarily SiO2 - Silicon Dioxide)

Banded Agate (specifically Sardonyx or Red Agate)

Silicon Dioxide (SiO2)

Rough Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Blue Sapphire

Corundum (Al2O3)

Yellow Chert (Chert/Jasper)

Silicon Dioxide (SiO2)

Basalt

Extrusive mafic igneous rock

Quartz / Quartzite

Silicon Dioxide (SiO2)

Magnetite

Magnetite (Iron(II,III) oxide, Fe3O4)

White Agate (Chalcedony)

Silicon Dioxide (SiO2)

Olivine (Peridot)

Olivine (Mg, Fe)2SiO4

Diamond (Colorless/White)

Carbon (C)

Green Kyanite

Kyanite (Al2SiO5)

Sandstone with Secondary Mineral Encrustation

Arenite with Silica/Calcite deposits (SiO2 or CaCO3)

Quartzite

Quartzite (composed primarily of SiO2)

Smoky Quartz

Smoky Quartz (SiO2 - Silicon Dioxide with trace impurities of aluminum)

Quartzite

Quartzite (primarily SiO2)

Rose Quartz

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

River Siltstone / Mudstone Pebble

Siltstone (composed of mixed silicate and carbonate minerals)

Smoky Quartz

Silicon Dioxide (SiO2)

Quartzite

Quartzite (primarily SiO2)

Orange Calcite (Polished Sphere)

Calcium Carbonate (CaCO3)

Pumice

Pumice (a highly vesicular volcanic rock)

Amethyst

Silicon Dioxide (SiO2 with iron impurities)

Chert (Green variety)

Microcrystalline Quartz (SiO2)

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Rose Quartz

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

Dolomite on Prehnite (Saddle-shaped Dolomite)

Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]

Pyrite

Iron Sulfide (FeS2)

Jasper (specifically Bloodstone or Heliotrope variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Anthracite Coal

Anthracite (Carbon-rich metamorphic rock)

Quartzite (River Cobble)

Quartzite (primarily SiO2)