Sedimentary (Man Made Conglomerate)

Iron Slag (Industrial Byproduct)

Anthropogenic Vitrification Product/Ferrous Slag

Polished black stone, likely obsidian

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

Puddingstone (Gowganda)

Gowganda Formation Conglomerate

Green obsidian (likely molded or heat-treated glass-like specimen)

Volcanic glass; predominantly rhyolitic composition (silica-rich amorphous SiO₂)

Quartz Pebble

Silicon Dioxide (SiO2)

Pet Rock (Man-made Quartzite or Granite Cobble)

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

Blue opal heart cabochon

Common opal, hydrated amorphous silica (SiO₂·nH₂O), likely blue-dyed or synthetic opalite

Slag (Industrial Glass/Glassy Rock)

Anthropogenic Vitreous Material

Sea Glass (White/Clear)

Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO

Aura Quartz

Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)

Red Slag Glass

Amorphous Silica (Industrial byproduct with metallic oxide dopants)

Puddingstone

Conglomerate (Gowganda Formation)

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).

Conglomerate (or Breccia)

Clastic Sedimentary Rock

Green sea glass or tumbled green quartz (uncertain)

Likely quartz (SiO₂) if natural; alternatively man-made soda-lime glass

Quartz pebble

Silicon dioxide (SiO2)

Botryoidal chalcedony (likely agate/jasper variety)

Microcrystalline quartz, SiO₂

Polished silver sheen obsidian heart

Obsidian (volcanic glass), primarily rhyolitic silica-rich glass

Note: This is a Man-Made Object (Costume/Prop Patch)

Synthetic fiber and pigments (Cellulose/Plastic-based composite)

Man-made Synthetic Material (Plastic/Composite)

Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)

Green Aventurine

Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)

Slag

Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)

Man-made Jewelry (Metal and Glass/Plastic)

Synthetic Alloy and Amorphous Solid (SiO2/Polymer)

Opalite

Synthetic Opalised Glass

Carborundum (Silicon Carbide)

Silicon Carbide (SiC)

Red-orange cabochon, likely carnelian or glass imitation

Carnelian: chalcedony (microcrystalline SiO₂), commonly iron-colored

Jasper Conglomerate

Clastic Sedimentary Rock (Conglomeratic Quartzite)

Quartz Conglomerate

Quartz Conglomerate (clastic sedimentary rock)

Polished black pebble, possibly obsidian

Volcanic glass (obsidian), likely; identification is tentative from the image

Conglomerate Pebble (with Chert / Quartz)

Sedimentary Conglomerate / Breccia Pebble

Conglomerate with Quartzite Pebbles

Clastic sedimentary rock (Conglomerate)

Conglomerate (pebble-to-cobble gravel)

Polymictic conglomerate; clast-supported conglomerate in a sandy or silty matrix

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Titanium Amethyst Geode

Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer

Ferruginous Conglomerate

Ferruginous Conglomerate (Clastic Sedimentary Rock)

Conglomerate (Puddingstone)

Conglomerate (specifically, clastic sedimentary rock)

Quartzite in Conglomerate

Clastic Sedimentary Rock with Silicon Dioxide (SiO2) inclusions

Green Glass (often marketed as 'Obsidian' or 'Green Quartz')

Amorphous Silica (SiO2) with copper or chromium additives

Gravel / Small Pebble

Rock Fragment (Gravel)

Quartz Pebble

Silicon dioxide (SiO2)

Blue-green cabochon, likely chalcedony or treated glass imitation

Cryptocrystalline quartz (chalcedony/possibly chrysoprase); identification uncertain from image

Blue Obsidian

Volcanic Glass (SiO2 with inclusions)