Man Made Glass (Often Grouped With Minerals In Lapidary)

Faceted clear gemstone, likely quartz or glass imitation

Most likely quartz (SiO₂); exact identification requires refractive-index and hardness tests

Nickel coin (U.S. currency)

Cupronickel (75% Copper, 25% Nickel alloy)

Granodiorite

Granodiorite

Slag Glass (Cullet)

Amorphous Silica / Glass residue

Concrete Fragment

Hardened Portland cement and mineral aggregate

Tumbled black obsidian (likely)

Volcanic glass; chiefly silica-rich rhyolitic glass (SiO₂)

Clay (as a rock-forming material)

Clay minerals (e.g., Kaolinite group, Smectite group, Illite group, Chlorite group)

Quartzite (Engineered Stone)

Silicon Dioxide (SiO2) based synthetic composite

Carborundum

Silicon Carbide (SiC)

Pyrite Concretion (Grapestone)

Iron Sulfide (FeS2) Concretion

Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)

Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)

Smelter Slag

Anthropogenic Silicate Slag

Cullet (Slag Glass)

Amorphous Silica (Industrial byproduct)

Crackle Glass (Simulated Gemstone)

Amorphous Solid (SiO2)

Possible obsidian or slag glass

Volcanic glass, primarily SiO₂; alternatively industrial iron-rich glassy slag

Goldstone

N/A (Synthetic Glass with Copper Inclusions)

Asphalt (Bituminous Concrete)

Bituminous mix containing aggregates and petroleum-based binder (CnH2n+2)

Possible sea glass (naturally frosted glass), not a confirmed geological specimen

Man-made silicate glass; composition varies, commonly soda-lime glass

Dyed or synthetic turquoise-blue glass-like specimen

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

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).

Blue Sapphire (Synthetic or Man-made Glass Imitation)

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

Likely polished quartz or glass-like mineral cabochon

Probably quartz (SiO₂), though the image cannot exclude man-made glass

Aura Quartz

Silicon Dioxide (SiO2) with metallic vapor coating

Aura Quartz (Titanium-coated Quartz)

Silicon Dioxide (SiO2) with metallic vapor coating

Blue opal heart cabochon

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

Cubic Zirconia

Cubic Zirconium Dioxide (ZrO2)

Likely iron-rich slag or weathered ironstone fragment

Uncertain; possibly iron oxide–rich material (hematite/goethite) or industrial iron slag

Goldstone (Brown)

Aventurine glass

Slag Glass (Cullet)

Amorphous Silica (man-made), primarily SiO2 with trace metal oxides

Polished black stone, likely black obsidian

Obsidian (volcanic glass), chiefly silica-rich rhyolitic composition

Conglomerate

Conglomerate Rock (Paraconglomerate)

Aura Quartz (specifically Titanium Aura Quartz)

Titanium-coated Silicon Dioxide (SiO2 + Ti Coating)

Blue-green cabochon, likely chalcedony or treated glass imitation

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

Chalcedony on Matrix

Silicon Dioxide (SiO2)

Stainless Steel (Polished)

Ferrous Alloy containing Iron (Fe), Chromium (Cr), and Carbon (C)

Titanium Aura Quartz

Titanium bonded Silicon Dioxide (SiO2 + Ti)

Milky Quartz with Chlorite inclusion

Silicon Dioxide (SiO2) with Chlorite group inclusions

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Brick fragment (Man-made material)

N/A (Fired clay)

Carborundum (Silicon Carbide)

Silicon Carbide (SiC)

Carved serpentine pendant

Serpentine-group minerals, commonly antigorite/lizardite (Mg₃Si₂O₅(OH)₄), possibly mixed with chlorite or other inclusions

Blue Crackle Quartz (Dyed Quarzite)

Silicon Dioxide (SiO2) with artificial dye