Amethyst (Faceted)

Amethyst (Silicon Dioxide with iron impurities, SiO2)

mineral

Diamond (or Cubic Zirconia simulant)

Carbon (C) - Diamond / Zirconium dioxide (ZrO2) - CZ

mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

mineral

Blue Sapphire

Corundum (Al2O3 with trace Titanium and Iron)

mineral

Blue Sapphire

Corundum (Al2O3)

mineral

Green Aventurine (Quartz)

Silicon Dioxide (SiO2) with inclusions of Fuchsite

metamorphic

Citrine

Silicon dioxide (SiO2)

mineral

Citrine

Silicon dioxide (SiO2)

mineral

Aragonite

Aragonite (Calcium Carbonate - CaCO3)

mineral

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide , SiO2)

igneous

Charoite

Charoite (Hydrated potassium, sodium, calcium, barium, strontium silicate hydroxide fluoride)

metamorphic

Carnelian (Red Chalcedony)

Silicon Dioxide (SiO2)

mineral

Herkimer Diamond

Double-terminated Quartz (Silicon Dioxide, SiO2)

mineral

Orange Calcite

Calcium Carbonate (CaCO3)

mineral

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary

Amethyst

Quartz (Silicon Dioxide with Iron impurities), SiO2

mineral

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

metamorphic

Pyrite

Iron Sulfide (FeS2)

mineral

Rose Quartz

Silicon dioxide (SiO2) with trace impurities of titanium, iron, or manganese

mineral

Dendritic Agate

Silicon Dioxide (SiO2) with Manganese or Iron Oxide inclusions

mineral

River Rock (Basalt/Greywacke)

Aphanitic Basalt or Lithic Sandstone (Greywacke)

igneous

Sandstone (Ferruginous)

Sandstone (primarily SiO2 with Iron Oxide cement)

sedimentary

Basalt

Basalt (comprising plagioclase, pyroxene, and olivine)

igneous

Chert (with Quartz Vein)

Chert (Siliceous sedimentary rock, predominantly Microcrystalline Quartz SiO2)

sedimentary

Sandstone Pebble

Arenite (primarily SiO2)

sedimentary

Scoria (Red Lava Rock)

Scoria

igneous

Scoria (Lava Rock)

Scoria

igneous

Scoria (Red Lava Rock)

Scoria

igneous

Scoria (Red Lava Rock)

Scoria

igneous

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

mineral

Quartzite Pebble

Metamorphic Quartzite (SiO2)

metamorphic

Moonstone (Green Moonstone / Garnierite)

Potassium Aluminum Silicate (KAlSi3O8) with inclusions of Garnierite

mineral

Smoky Quartz (Polished)

Silicon Dioxide (SiO2)

mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

mineral

Gneiss (Granitic Gneiss)

Gneiss

metamorphic

Red Jasper (possibly Chert/Argillite)

Jasper (SiO2) with iron oxide inclusions

sedimentary

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)

metamorphic

Gneiss (Schistose)

Gneiss

metamorphic

Chert (including Flint and Jasper variants)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

sedimentary

Chert (Flint)

Chert (SiO2)

sedimentary

Quartz (Engineered Quartz Surface)

Silicon Dioxide (SiO2) based composite

mineral (man-made composite)

Quartz with Iron Staining

Silicon Dioxide (SiO2) with FeOx inclusions

mineral