Mineraloid (Man Made Glass)

Limonite/Ironstone

Limonite (FeO(OH)·nH2O)

Milky quartz pebble

Quartz, silicon dioxide (SiO₂)

Blue glassy cabochon, likely blue quartz or synthetic glass

Possibly dyed blue chalcedony/quartz (SiO₂); visual identification is inconclusive

Likely milky quartz fragment

Quartz (SiO₂)

Obsidian

Volcanic glass

Tumbled orange-and-white feldspar-rich stone, likely sunstone or orange feldspar

Likely potassium feldspar (orthoclase or microcline), KAlSi₃O₈; exact identification is uncertain from the image

Limonite (Iron Ore)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Jet

Lignite (Anthracite-grade compact coal)

Black tumbled stone, possibly obsidian

Obsidian (natural volcanic glass; composition varies, typically silica-rich)

Chert (Flint)

Silicon Dioxide (SiO2)

Tumbled amber

Amber (fossilized plant resin), commonly succinite; organic mineraloid

Polished amethyst-bearing quartz

Quartz, SiO₂; purple coloration from irradiation and trace iron

Nickel coin (U.S. currency)

Cupronickel (75% Copper, 25% Nickel alloy)

Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Red glass-like crystal, likely synthetic ruby or red glass

Uncertain from image; possible corundum (ruby), Al₂O₃, or synthetic glass

Opal (in Jewelry Setting)

Hydrated Silicon Dioxide (SiO2·nH2O)

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Native Silver

Silver (elemental Ag)

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Granodiorite

Granodiorite

Beaded gemstone bracelet

Indeterminate; likely small polished mineral beads, possibly turquoise or dyed stone, with metal and glass components

Opal

Hydrated Silica (SiO2·nH2O)

Limonite (Ironstone)

Limonite (mixture of hydrated iron(III) oxide-hydroxides)

Tumbled blue chalcedony (possibly blue agate)

Microcrystalline quartz, SiO₂; chalcedony variety

Obsidian

Volcanic glass (SiO2)

Polished, carved gemstone (possibly dyed agate or glass-like material)

Unconfirmed from the image; no specific mineral can be identified reliably

Green Aventurine

Silicon Dioxide (SiO2+KAl2(AlSi3O10)(OH)2)

Red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored chiefly by iron oxides

Red agate bead (likely dyed or treated)

Agate, a microcrystalline variety of quartz; SiO₂

Red Sandstone

Clastic Sedimentary Mineraloid (predominantly Quartz grains with Iron Oxide cement)

Clear crystal-bead bracelet, possibly quartz

Unidentified transparent mineral beads; quartz (SiO₂) is one possibility

Green obsidian (likely moldavite)

Natural volcanic glass; if extraterrestrial-impact glass, moldavite (tektite)

Tumbled green glassy mineral, possibly aventurine or fluorite

Uncertain; likely quartz variety (aventurine quartz, SiO₂) or green fluorite (CaF₂)

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Black Pearl (Tahitian Pearl)

Aragonite / Calcite (CaCO3) with Conchiolin

Chert

Chert (Microcrystalline Quartz)

Opal

Hydrated silica (SiO2 "NH2O)

Amber

Amber (C10H16O)

Opal

Hydrated amorphous silica (SiO2·nH2O)

Colorless faceted gemstone, likely quartz

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

Red cabochon gemstone ring (likely ruby or red spinel; identity unconfirmed)

Possibly corundum (ruby, Al₂O₃) or spinel (MgAl₂O₄); visual identification alone cannot distinguish these from glass or synthetic stones.

Pink Opal

Hydrated amorphous silica (SiO2·nH2O)