Anthropogenic (Man Made Material Processed By Nature)

Polished black stone, likely obsidian

Obsidian (volcanic glass; mostly silica-rich rhyolitic composition)

Green Agate

Silicon dioxide (SiO₂)

Eroded Brick or Pumice-like Scoria

Vesicular Basalt / Scoria (Anthropogenic variant: Eroded Firebrick)

Polymictic conglomerate or breccia (possibly concrete-like aggregate)

Lithified polymictic gravel; clasts may include basalt, granite, quartzite, and other silicates

Ironstone Concretion (Pot Stone)

Siderite or Limonite Concretion (FeCO3 or FeO(OH)·nH2O)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Sea Glass

Man-made silicate glass (Amorphous silicon dioxide)

Goldstone (brown goldstone)

Man-made aventurine glass, typically copper-bearing silica glass

Glass / Silicon Dioxide (Man-made)

SiO2 (Amorphous Silicon Dioxide)

Angel Aura Quartz (Treated Clear Quartz)

Silicon Dioxide (SiO2) coated with Vaporized Silver and Platinum

Opalite

Synthetic Glass (SiO2 + impurities)

Coquina

Bioclastic Limestone

Quartz crystal fragment (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Dalmatian Stone

Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)

Small rounded mineral pebble, possibly quartz

Uncertain; likely microcrystalline or crystalline SiO₂ (quartz), potentially with iron-oxide staining

Concretion with Geode Cavity

Ferruginous Sandstone Concretion with Quartz Center

Blue Sapphire (Synthetic or Man-made Glass Imitation)

Corundum (Al2O3) if natural; Lead-glass or Spinal if synthetic

Opalite

Synthetic Opalized Glass / Man-made Glass

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), opaque-to-translucent milky variety

Iron-rich vesicular rock, possibly slag or weathered basalt

Identification uncertain; likely ferruginous basalt/ironstone, with possible anthropogenic iron slag

Goldstone

Man-made glass containing cuprous oxide

Goldstone

Man-made glass infused with copper particles

Man-made Glass (Tumbled/Shaped)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Goldstone (aventurine glass)

Man-made copper-bearing glass; not a natural mineral (commonly sold as blue/brown goldstone)

Gemstone jewelry ensemble

Likely mixed gemstone and glass-bead jewelry; exact stones cannot be determined from the image

Engineered Quartz Stone

Agglomerated Quartz (SiO2 + Polymer Resin)

Tumbled milky quartz

Quartz — silicon dioxide (SiO₂), cryptocrystalline or microcrystalline variety possible

Felsic Drill Core (likely Gneiss or Granite)

Felsic Metamorphic Rock (Gneissic profile)

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2AlSi3O10(OH)2)

Acrylic or Resin (Synthetic Imitation)

Polymethyl Methacrylate (PMMA) or Polyepoxide

Slag Glass (Cullet)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Crackle Agate / Dyed Quartz

SiO2 (Silicon Dioxide)

Goldstone (likely red/brown aventurine glass)

Man-made aventurine glass; copper-bearing silicate glass (not a natural mineral)

Coquina

Biogenic Limestone (Calcite/Aragonite base, CaCO3)

Man-made Jewelry Charm (Enameled Metal)

Not a natural mineral; composed of base metal alloy (likely zinc or brass) and epoxy resin/enamel.

Ferrous Slag (Iron Smelting By-product)

Fused Siliceous Slag

Opalite

Synthetic Glass (typically Silica/Magnesium based with metal additives)

Black Tourmaline

Schorl (NaFe2+3Al6(Si6O18)(BO3)3(OH)4)

Green Aventurine

SiO2 (Silicon Dioxide with Fuchsite inclusions)

Possible weathered basalt or slag fragment

Basalt, chiefly plagioclase and pyroxene; identification is uncertain from the image

Dyed or synthetic turquoise-blue glass-like specimen

Likely man-made colored glass or resin; exact identification requires testing

Opalite

Synthetic Opalized Glass (SiO2 + additives)