Man Made Mineral Simulant (Glass)

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Man-made Glass (Tumbled/Shaped)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Titanium Amethyst Geode

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

Diamond (or Cubic Zirconia)

Carbon (C) or Zirconium Dioxide (ZrO2)

Dyed Aura Quartz

Silicon Dioxide (SiO2) with metallic coating

Asphalt (Bituminous pavement)

Bituminous concrete / Asphalt

Cullet Glass (Man-made Glass Slag)

Amorphous Silica (SiO2) with chemical additives

Diamond (or Diamond Simulant)

Carbon (C) if diamond, various if simulant (e.g., Cubic Zirconia ZrO2)

Aura Quartz

Titanium/Titanium-Gold treated Silicon Dioxide (SiO2)

Granite with Cupules / Bedrock Mortars

Granite (felsic intrusive plutonic rock)

Chert Concretion (with typical hematite/limonite staining)

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

Conglomerate

Conglomerate (Sedimentary rock containing rounded clasts)

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).

Smelter Slag

Anthropogenic Silicate Slag

Opalite (a synthetic glass, often confused with Opal)

Silicon dioxide glass (SiO2nH2O, for natural opal)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2)

Dyed Blue Agate (Dragon Vein Agate)

Silicon Dioxide (SiO2) with artificial cobalt/organic dyes

Diamond

Native Carbon (C)

Asphalt Chunk

Asphalt concrete

Hematite

Iron(III) oxide (Fe2O3)

Diamond

Carbon (C)

Diamond (or synthetic simulant)

Cubic C (Carbon)

Blue goldstone beads

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

Man-made earbud charging case (Not a rock or mineral)

Acrylonitrile Butadiene Styrene (ABS) Plastic with electronic components

Weathered iron-rich concretion or ironstone nodule

Goethite–hematite limonite concretion (FeO(OH), Fe₂O₃, and hydrated iron oxides)

Ruby (Faceted)

Corundum (Al2O3:Cr)

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

Glass / Silicon Dioxide (Man-made)

SiO2 (Amorphous Silicon Dioxide)

Ceramic or Polished Stone Heart (Anthropogenic Material)

Glazed Ceramic (Silicon Dioxide based coating on Alumina Silicate body) or Polished Limestone/Marble (Calcium Carbonate, CaCO3)

Dyed Agate / Painted Stone

Silicon Dioxide (SiO2) with artificial pigment

Cultured Marble (Synthetic)

Polymer-matrix composite (typically calcium carbonate in polyester resin)

Green Sea Glass

Amorphous Silica (man-made glass), SiO2 + additive metal oxides

Diamond (or Diamond Simulant)

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

Faceted Clear Quartz or Diamond Simulant

Silicon Dioxide (SiO2) if Quartz or Cubic Zirconia (ZrO2) if Synthetic

Diamond (or Diamond Simulant)

Carbon (C)

Ferruginous Conglomerate (or Iron-Rich Concrete/Slag)

Clastic Sedimentary (Silicon Dioxide/Iron Oxide matrix)

Red Sandstone or Brick Fragment

Arenite (if sandstone)

Polished blue calcite sphere (tentative identification)

Calcite, CaCO₃; blue color generally results from trace impurities or inclusions

Cubic Zirconia (Man-made)

Cubic Zirconia (ZrO2) with Enamel and Metal Alloy

Goldstone (Brown)

Aventurine glass

Faceted Clear Gemstone (Likely Quartz or Cubic Zirconia)

Silicon Dioxide (SiO2) or Zirconium Dioxide (ZrO2)

Crescent Pebble

Weathered Quartzite or Sandstone Fragment