Organic Gem Material (Botanical)

Jasper

Microcrystalline Quartz (SiO2)

Jasper

Microcrystalline Quartz (SiO2)

Chert Nodules (with Flint core)

Microcrystalline Quartz (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Sandstone

Arenite

Sandstone

Arenite

Onyx (Black) and Mother of Pearl Inlay

Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Weathered granite or granitic gneiss

Quartz–feldspar–mica aggregate; possibly foliated granitic gneiss

Smoky Quartz with Feldspar

SiO2 (Quartz) with KAlSi3O8 (Feldspar)

Light-colored weathered rocks, possibly limestone or quartz-rich stone

Probable limestone/calcitic rock; exact identification is uncertain because strong flash overexposure obscures texture

Iron-stained sandstone or weathered ironstone

Quartz-rich sandstone with iron-oxide cement, chiefly hematite (Fe₂O₃) and/or goethite (FeO(OH))

Amethyst

SiO2 (Silicon Dioxide) - Purple variety of Quartz

Red garnet (likely almandine or pyrope)

Garnet-group nesosilicate; commonly almandine, Fe₃Al₂(SiO₄)₃, or pyrope, Mg₃Al₂(SiO₄)₃

Blue slag-like mineral specimen, possibly bornite or chalcopyrite

Tentatively bornite (Cu5FeS4) or iridescent chalcopyrite (CuFeS2)

Quartz

Silicon Dioxide (SiO2)

Faceted colorless gemstone, likely diamond

Diamond (crystalline carbon, C)

Likely raw garnet crystal

Garnet-group silicate, probably almandine (Fe₃Al₂Si₃O₁₂)

Colorless faceted gemstone, likely quartz

Quartz (SiO₂), tentative identification; the photo is insufficient to confirm the material

Petrified Wood

Silicified wood (SiO2)

Faceted yellow gemstone, possibly citrine

Unconfirmed from the image; if citrine, it is iron-colored quartz (SiO₂).

Tumbled aquamarine

Beryl, Be₃Al₂Si₆O₁₈ (blue-green variety)

Pegmatite with quartz, feldspar, mica, and tourmaline

Granitic pegmatite; chiefly quartz (SiO₂), feldspar, muscovite, and black schorl tourmaline (NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Olivine

Olivine group (Mg, Fe)2SiO4

Olivine (Peridotite)

(Mg,Fe)2SiO4 (Magnesium Iron Silicate)

Olivine (Peridotite)

Olivine Group; (Mg, Fe)2SiO4

Fossil bivalve shell

Likely an extinct or modern-like ribbed cockle/scallop; exact genus requires locality and diagnostic hinge features

Weathered quartz-rich pebble

Likely quartzite or milky vein quartz; exact identification is uncertain from the image

Fossiliferous Limestone

Calcite (CaCO3) matrix with biogenic fragments

Mother of Pearl (Nacre) / Shell Fragment

Biogenic Calcium Carbonate (Aragonite and Conchiolin)

Quartz-rich pegmatite (likely rose/iron-stained quartz)

Quartz, SiO₂, in a coarse granitic pegmatite matrix; possibly with feldspar and mica

Aura Turquoise or Treated Turquoise Beads

Hydrated copper and aluminum phosphate (CuAl6(PO4)4(OH)8·4H2O) with metallic coating

Faceted blue gemstone, likely aquamarine

Aquamarine—blue beryl, Be₃Al₂Si₆O₁₈; identification is uncertain from the image alone

Chert (Flint)

Silicon Dioxide (SiO2)

Banded Chert

Silicon Dioxide (SiO2)

Blue-gray kyanite crystal

Kyanite (Al₂SiO₅)

Tumbled beige stone, possibly quartz or calcite

Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)

Green tourmaline (likely chrome/dravite tourmaline crystals)

Tourmaline-group cyclosilicate; commonly elbaite, dravite, or chromdravite, complex borosilicate formula

Chert (Flint)

Silicon Dioxide (SiO2)

Dark cabochon gemstone, likely labradorite

Labradorite, plagioclase feldspar (approximately NaAlSi₃O₈–CaAl₂Si₂O₈)

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with fossil inclusions

Chert Pebble

Cryptocrystalline Quartz (SiO2)