Man Made Material (Jewelry, Metal Alloy)

Faceted brown gemstone ring, likely smoky quartz

Smoky quartz (SiO₂), identification uncertain from the image

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Quartz (likely milky quartz or quartz glass-like fragment)

Quartz, silicon dioxide (SiO₂)

Faience and Carnelian in Egyptian Revival Jewelry

Faience (quartz frit) and Carnelian (chalcedony, SiO2)

Polished banded agate pendant

Agate, microcrystalline quartz (SiO₂), a chalcedony variety

Black tumbled stone, possibly obsidian

Obsidian (volcanic glass; predominantly SiO₂), identification uncertain from image

Faceted clear gemstone in a gold-tone ring

Likely colorless quartz (SiO₂); the image does not establish the stone identity, and glass or another gem is possible

Green faceted gemstone pendant, likely green quartz

Quartz (SiO₂), possibly prasiolite or green-treated quartz

Tumbled black obsidian (likely)

Volcanic glass; chiefly silica-rich rhyolitic glass (SiO₂)

Dyed Dragon Vein Agate

Silicon Dioxide (SiO2) with artificial pigment

Celestite (Celestine)

Strontium Sulfate (SrSO4)

Celestite (Celestine)

Strontium Sulfate (SrSO4)

Celestite (Celestine)

Strontium sulfate (SrSO4)

Fluorite (Polished Point/Tower)

Calcium Fluoride (CaF2)

Weathered metallic meteorite (probable iron meteorite)

Fe–Ni alloy, mainly kamacite and taenite; exact classification requires chemical and petrographic testing

Clear quartz crystal pendant

Quartz (silicon dioxide, SiO₂)

Blue-dyed tumbled quartz or glass imitation

Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image

Michigan Float Copper

Native Copper (Cu)

Iron Meteorite

Iron-Nickel Alloy (Kamacite and Taenite)

Ferruginous Sandstone (Gozzan)

Iron-rich clastic sedimentary rock with Limonite/Goethite

Turquoise bead bracelet

Turquoise, hydrated copper–aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O (bead material may be stabilized or dyed)

Pink coral and green-stone jewelry

Likely pink coral (calcium carbonate, CaCO₃) set with an unidentified green stone; the image is too indistinct to identify the green material reliably.

Pet Rock (Man-made Quartzite or Granite Cobble)

Silicon dioxide (SiO2) mixture; commonly composed of Quartz, Feldspar, and Mica

Green faceted gemstone earrings

Undetermined; possibly green glass or synthetic emerald-type material, rather than identifiable natural emerald

Polished iron meteorite fragment

Iron meteorite, chiefly kamacite and taenite (Fe–Ni alloys), possibly weathered or etched

Diamond

Carbon (C)

Dyed Crackle Quartz

Silicon Dioxide (SiO2) with synthetic dye

Clear faceted gemstone in an ornate ring (likely quartz or glass imitation)

Unidentified colorless faceted stone; visual identification is inconclusive

Cupronickel (on a 1981 Mexico 20 Pesos coin)

Copper-Nickel Alloy (Cu75Ni25)

Inlaid turquoise and red-stone earrings

Likely turquoise (CuAl₆(PO₄)₄(OH)₈·4H₂O) with an unidentified red inlay; the image does not establish the materials

Quartz crystal (likely clear quartz)

Quartz, silicon dioxide (SiO₂)

Sandstone Anvil / Nutting Stone

Quartzose Sandstone (Sedimentary Rock)

Quartzite (Engineered Stone)

Silicon Dioxide (SiO2) based synthetic composite

Chert Concretion (with typical hematite/limonite staining)

Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Pyrite Concretion (Grapestone)

Iron Sulfide (FeS2) Concretion

Green Agate

Silicon dioxide (SiO₂)

Polished brecciated jasper pendant

Silica-rich jasper (microcrystalline quartz, SiO₂), brecciated and cemented by silica or iron-rich material

Cut faceted gemstone, possibly diamond or quartz

Uncertain from the blurred image; diamond is crystalline carbon (C), while quartz is silicon dioxide (SiO₂)

Pavé-set diamond ring

Diamond (crystalline carbon, C)

Tumbled green fluorite

Fluorite (calcium fluoride, CaF₂)

Diamond (in a jewelry setting)

Cubic Carbon (C)