Industrial By Product

Kaolin (China Clay)

Kaolinite [Al2Si2O5(OH)4]

Opalite (Synthetic Moonstone/Opal)

Synthetic Silica Glass

Hematite or Goethite-rich Ironstone

Ironstone (Oxidized Iron Ore)

Man-made Blank Ammunition (Brass)

CuZn (Cartridge Brass - roughly 70% Copper, 30% Zinc)

Diamond-set earring

Diamond (carbon, C); crystal structure: cubic

Chert / Jasper

Silicon Dioxide (SiO2)

Faceted Clear Gemstone (Likely Quartz or Cubic Zirconia)

Silicon Dioxide (SiO2) or Zirconium Dioxide (ZrO2)

Diamond (or Diamond Simulant)

Carbon (C) or Zirconium dioxide (ZrO2) for CZ

Diamond (or Simulant)

Carbon (C) or Cubic Zirconia (ZrO2)

Diamond

C

Silver Nugget

Native Silver (Ag)

Coal

Combustible sedimentary rock

Agate

Silicon Dioxide (Chalcedony), SiO2

River Pebble (Quartzite/Chert)

Quartzite with inclusions (SiO2)

Quartzite

Quartzite (SiO2)

Porphyritic Andesite

Andesite (Intermediate Volcanic Rock)

Slag

Metallurgical Slag

Quartzite

Quartzite (SiO2)

Tumbled White Quartz

Silicon Dioxide (SiO2)

Gravel and Sediment Sample

Mixed clastic sediment

Diamond (or Lab-Grown Cubic Zirconia)

Carbon (C)

Baroque cultured pearl necklace

Pearl: nacre composed mainly of aragonite (CaCO₃) and conchiolin

Small rounded pebble, likely porous volcanic rock

Possibly vesicular basalt or scoria; exact identification is not possible from the image alone

Silicon (Industrial Grade)

Elemental Silicon (Si)

Quartz Pebble

Silicon Dioxide (SiO2)

Iron-rich sulfide-bearing rock, likely pyrite-rich shale or limonite-goethite specimen

Likely pyrite (FeS₂) with oxidation products goethite/limonite (FeO(OH)·nH₂O), possibly in shale or quartz matrix

Red Garnet

Almandine Garnet (Fe3Al2(SiO4)3)

Tumbled black stone, likely black obsidian

Obsidian — volcanic glass, primarily SiO₂

Rough Diamond

Diamond (pure Carbon, C)

Aura Quartz (Coated Quartz)

Silicon Dioxide (SiO2) treated with metallic vapor

Gravel or Crushed Stone

Fragmented Aggregate Stone

Chert Nodule (Flint)

Microcrystalline Quartz (SiO2)

Dark gray rock fragment

Indeterminate from image; possibly weathered basalt or fine-grained metamorphic rock

Black pebble, likely basalt

Basalt, fine-grained mafic volcanic rock; possibly weathered basaltic glass

Concretion or weathered iron-rich rock

Likely limonite/goethite-rich concretion; exact identification requires testing

Rounded pale-green pebble, likely serpentinite or altered basalt

Probable serpentinite (serpentine-group minerals) or weathered mafic rock; exact identification requires testing

Polished dark pebble, likely basalt

Basalt; fine-grained mafic rock dominated by plagioclase and pyroxene, commonly with olivine

Man-made Slag (Industrial Byproduct)

Anthropogenic Glassy Residue

Ironstone (Limonitic Shale)

Ferruginous Siltstone / Goethite-rich Sedimentary Rock

Potassium-Rich Silicate Clay (inferred from biological context)

Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)

Quartzite

Quartzite (primarily SiO2)

Mica (Muscovite)

Muscovite, KAl2(AlSi3O10)(OH)2