Anthropogenic (Man Made Material Mimicking Sedimentary Rock)

Metal Alloy (Likely Pewter or Sterling Silver)

Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).

Ironstone Concretion

Ironstone (primarily Siderite or Limonite)

Rainbow Hematite Ring

Iron(III) oxide (Fe2O3) with thin-film coating

Sea Glass

Man-made silicate glass

Sea Glass

Man-made silicate glass

Blue-green faceted gemstone, possibly glass or synthetic material

Not identifiable from the image; possible synthetic spinel or glass

Titanium Coated Kyanite (Aura Kyanite)

Aluminosilicate (Al2SiO5) with a Titanium-Niobium vacuum-deposited coating

Sea Glass

Man-made silicate glass

Gastropod Internal Mold (Steinkern)

Class Gastropoda fossil mold (Phylum Mollusca)

Opalite

Synthetic Glass (Hydrated Silica Simulant)

Red goldstone beads

Goldstone (man-made copper-bearing glass; not a natural mineral)

N/A - Image does not contain a rock or mineral

Anthropogenic textile material

Nutting Stone / Cupstone (Sandstone or Quartzite)

Sedimentary rock with anthropogenic modification (cupule)

Red-orange jasper pebble (tentative)

Microcrystalline quartz, SiO₂, colored mainly by iron oxides

Opalite

Man-made opalescent glass

Blue Obsidian (Cullet Glass)

Silicon Dioxide (Amorphous Glass)

Clear Quartz Sphere (Rock Crystal)

Silicon Dioxide (SiO2)

Mohave Turquoise (Composite/Stabilized)

Hydrated copper aluminium phosphate (CuAl6(PO4)4(OH)8·4H2O) with stabilizing resin and metallic inclusions

Opalite (Synthetic Moonstone/Sea Opal)

Silicon Dioxide (SiO2) glass with metallic inclusions

Blue Obsidian

Volcanic Glass (SiO2 with inclusions)

Green sea glass (likely)

Anthropogenic glass, not a mineral; composition commonly soda–lime silicate glass

Blue cabochon gemstone, likely synthetic glass or dyed stone

Indeterminate from image; possible glass, synthetic spinel, sodalite, or lapis lazuli

Quartz pebble (Quartztite fragment)

Silicon Dioxide (SiO2)

Painted River Rock

Anthropogenic-modified Siliciclastic Sedimentary Rock

Man-made Synthetic Material (Costume Faux Fur)

Synthetic Polymer (Polyester/Acrylic)

Polished obsidian

Volcanic glass; predominantly rhyolitic SiO₂

Red glassy gemstone, possibly garnet

Unidentified red transparent material; garnet group (X₃Y₂(SiO₄)₃) is a possibility

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Rounded graywacke or sandstone cobble

Lithified clastic sandstone; likely quartz–feldspar–lithic grain aggregate in a silica or calcite matrix

Green sea glass (likely slag glass or bottle glass)

Man-made soda-lime silicate glass; not a naturally occurring mineral

Opalite (a synthetic glass)

Silicon Dioxide (SiO2) with various additives; not a true mineral but a man-made gem simulant

Slag (Anthropogenic Glass/Iron byproduct)

Ferro-silicate Slag

Glass

Amorphous Silicon Dioxide (SiO2)

River Pebble / Chert Pebble

Microcrystalline Quartz (SiO2)

Goldstone (aventurine glass)

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

Brick veneer, likely manufactured from clay-rich shale

Fired clay brick; chiefly aluminosilicate minerals, commonly mullite and glassy silicate phases after firing

Quartz (Engineered Stone Countertop)

Silicon Dioxide (SiO2) with polymer resins

Chert Concretion (with typical hematite/limonite staining)

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

Carved opalite pendant

Opalite (man-made opalescent glass; not a natural mineral)

Opalite

Man-made Opalized Glass (Synthetic Glass)

Polished brown jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide and other mineral inclusions