Sedimentary (Biogenic Sediment Or Biological Remain)

Gneiss

Gneiss

Agate (specifically a Yellow/Honey Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Quartz (Druzy/Macro-crystalline)

Silicon Dioxide (SiO2)

Turquoise

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

Clear Quartz

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Gneiss (Granitic Gneiss)

Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)

Yellow Agate / Chalcedony

Silicon Dioxide (SiO2)

Quartz / Rock Crystal

Silicon Dioxide (SiO2)

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Quartz Geode

Silicon dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Red Jasper

Silicon dioxide (SiO2) with iron inclusions

Satin Spar Selenite

Gypsum (CaSO4·2H2O)

Gneiss (Cobble)

Gneiss

Yellow Jasper (Chert variant)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (Jasper variety)

Cryptocrystalline quartz (SiO2)

Chert (Jasper/Flint variety)

Silicon dioxide (SiO2)

Precious Opal

Hydrated Silica (SiO2·nH2O)

Blue Chalcedony

Silicon Dioxide (SiO2)

Jasper with Agate Inclusions

Jasper (Silicon Dioxide, SiO2) with Chalcedony/Agate

Satin Spar (often marketed as Selenite)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Petrified Wood

Silicified wood (primarily SiO2)

Garnet (Almandine variety)

Almandine Garnet (Fe3Al2(SiO4)3)

Jasper with Iron Staining

Silicon Dioxide (SiO2) with Hematite (Fe2O3)

Pyrite

Iron Sulfide (FeS2)

Limonite with Trace Fossils

Hydrous Iron Oxide Mixture (FeO(OH)·nH2O)

Quartz (Milky/Crystalline)

Quartz (Silicon Dioxide, SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz with iron inclusions

Quartz (specifically Milky or Clear Quartz)

Silicon Dioxide (SiO2)

Chalcedony (Moonstone variant or White Agate)

Silicon Dioxide (SiO₂)

Green Calcite

Calcium Carbonate (CaCO3)

Chalcedony Nodule (Agate/Chert)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Gneiss

Gneiss

Biotite Gneiss

Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)

Clear Quartz

Silicon Dioxide (SiO2)

Imperial Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz with Mineral Inclusions

Orange Calcite (Cleavage Rhomb)

Calcite (Calcium Carbonate, CaCO3)