Not A Rock (Man Made Polymer)

Polished white chalcedony or quartz pendant

Microcrystalline quartz (chalcedony), SiO₂; exact identification is uncertain from the image

Iron Slag

Iron/Steel Slag (Ferrosilicate Glass)

Polished black stone, likely obsidian

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

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

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

Aura Quartz

Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)

Blue goldstone beads

Man-made aventurine glass (silica glass with metallic copper inclusions), not natural lapis lazuli

Green sea glass or tumbled green quartz (uncertain)

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

Botryoidal chalcedony (likely agate/jasper variety)

Microcrystalline quartz, SiO₂

Polished silver sheen obsidian heart

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

Blue-green cabochon, likely chalcedony or treated glass imitation

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

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

Polished black pebble, possibly obsidian

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

Vesicular basalt (weathered scoria)

Scoriaceous basalt; chiefly plagioclase, clinopyroxene, olivine, and iron-titanium oxides

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Titanium Amethyst Geode

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

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

Amorphous Silica (SiO2) with copper or chromium additives

Sea Glass

Amorphous silicon dioxide (Man-made glass weathered by nature)

Engineered Quartz

Silicon dioxide composite

Amber cabochon pendant

Amber (fossilized plant resin), chiefly polymerized diterpenoid resin

Blue glassy tumbled stone, likely blue chalcedony or slag glass

Chalcedony (microcrystalline SiO₂), possibly man-made blue glass

Sea Glass

Amorphous Silicon Dioxide (Man-made glass weathered by nature)

Milky quartz (rough fragment)

Quartz, silicon dioxide (SiO₂)

Hematite

Iron(III) oxide (Fe2O3)

Goldstone (Red)

Aventurine Glass (SiO2 + Cu)

Ferro-slag (Leland Blue/Slag Glass)

Anthropogenic Vitreous Silica (Industrial Slag)

Blue Crackle Quartz (Dyed Quarzite)

Silicon Dioxide (SiO2) with artificial dye

Dyed Blue Agate (Dragon Vein Agate)

Silicon Dioxide (SiO2) with artificial cobalt/organic dyes

Diamond

Native Carbon (C)

Dyed Aura Quartz

Silicon Dioxide (SiO2) with metallic coating

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)

Amber

Succinite (Carbon-based organic compound; approximate formula C10H16O)

Goldstone (blue/black aventurine glass)

Man-made aventurine glass; silica glass containing metallic copper or other glittering inclusions

Rhinestone (or glass crystal)

Silicon dioxide (if glass) / Various

Red-orange jasper pebble (tentative)

Microcrystalline quartz, SiO₂, colored mainly by iron oxides

Blue chalcedony (likely dyed or treated)

Microcrystalline quartz, SiO₂ (chalcedony)

Opalite

Synthetic glass (SiO2 + metal additions)

Tumbled milky chalcedony (likely common opalite-like quartz)

Chalcedony, microcrystalline SiO₂; possibly pale common opal, hydrated SiO₂·nH₂O

Bowling Ball (Brunswick T-Zone Deep Space)

Polyester resin / Polyurethane polymer

Green glass-like cabochon, likely synthetic glass or resin

Unidentified green transparent material; possibly molded glass, synthetic spinel, or resin

Raw quartz crystal

Quartz (silicon dioxide, SiO₂), likely milky or included quartz