Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)

Petrified Wood

Silicified Wood (SiO2)

Tumbled citrine or iron-stained quartz

Quartz (SiO₂), likely iron-oxide-stained or natural citrine

Quartz-rich pegmatitic rock, possibly rose quartz with mica

Granitic pegmatite; predominantly quartz (SiO₂), with feldspar and mica

Green Serpentine

Serpentine group (Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4

Amber

Succinite (Formula: C10H16O)

Mammoth Tooth

Mammuthus tooth fossil

Petrified Wood

Silicified Wood (SiO2 permineralization)

Jasper

Silicon dioxide (SiO2) with iron oxide inclusions

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Sandstone

Arenite

Amber

Succinite (C10H16O)

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Petrified Wood

Silicified Wood (SiO2)

Mosasaur Tooth

Mosasaurus sp.

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Vuggy Limestone

Calcium Carbonate (CaCO3) with Quartz/Calcite inclusions

Petrified Wood

Silicified Wood (Permineralized Lycopsid, Conifer, or Hardwood)

Coral Fossil (Scleractinia)

Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified wood (Quartz, Chalcedony, or Opal)

Jasper

Silicon Dioxide (SiO2)

Unidentified weathered rock fragment

Likely granitic or feldspathic rock; exact identification requires clearer imaging and testing

Quartz (Rose or Milky)

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Vivianite

Vivianite, Fe2+3(PO4)2·8H2O

Jasper

Microcrystalline Quartz (SiO2)

Tumbled turquoise

Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

Chrysocolla (Copper Ore matrix)

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)

Chert / Flint

Cryptocrystalline Quartz (Silicon Dioxide, SiO2)

Weathered quartz-rich river cobble, possibly quartzite

Quartzite (mostly microcrystalline SiO₂), tentatively identified

Diorite (Dalmatian Stone)

Intermediate Phaneritic Igneous Rock

Pyrite

Pyrite (FeS2)

Tumbled amethyst (likely)

Quartz, SiO₂; purple coloration from irradiation and iron impurities

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Quartz geode / iron-stained quartz vein rock

Quartz (SiO₂), likely with iron oxides and minor feldspar or host-rock minerals

Tumbled carnelian (likely chalcedony)

Carnelian, orange-red cryptocrystalline quartz (SiO₂), a variety of chalcedony

Chert (Flint Nodule)

Microcrystalline and Cryptocrystalline Quartz (SiO2)

Slate

Foliated Metamorphic Rock (composed primarily of silica and alumina with iron and magnesium)

Quartz-rich rock, possibly milky quartz

Quartz (silicon dioxide, SiO₂), possibly with feldspar or mica inclusions