Mineraloid (Human Made Geological Specimen)

Blue-green slag glass or chalcedony-like material

Likely industrial glassy slag; exact identification requires testing

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Polished black stone, possibly black jasper or obsidian

Uncertain; candidates include microcrystalline quartz (SiO₂; black jasper) or volcanic glass (obsidian, SiO₂)

Tiger’s eye beads

Tiger’s eye (quartz variety), SiO₂, with pseudomorphic fibrous crocidolite/goethite inclusions

Gold bullion bars

Native gold (Au), likely cast or refined metal

Obsidian (Blue)

Volcanic Glass (SiO2)

Quartzite (Lithic Artifact)

Quartzite (SiO2)

Blue-beaded gemstone jewelry, likely lapis lazuli or dyed blue agate

Uncertain from the image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or blue chalcedony (SiO₂)

Tumbled green aventurine (likely)

Quartz (SiO₂) with fuchsite or other mica inclusions

Rock crystal (clear quartz), likely rough or lightly polished

Quartz — silicon dioxide (SiO₂)

Cullet (Slag Glass)

Amorphous Silica (SiO2) with various metal oxide colorants

Polished druzy quartz specimen

Quartz (SiO₂), likely druzy quartz with possible blue chalcedony or inclusions

Gemstone-set ring, likely cubic zirconia or diamond

Likely synthetic cubic zirconia (zirconium dioxide, ZrO₂); stones may alternatively be diamond (carbon, C)

Unidentified polished dark gemstone cabochon

Possibly hematite, obsidian, jet, or dark agate; image insufficient for a definitive identification

Green aventurine pendant

Quartz variety, SiO₂, colored mainly by fuchsite or other chromium-bearing mica inclusions

Tumbled milky quartz

Quartz, silicon dioxide (SiO₂)

Chert (Lithic Artifact)

Microcrystalline Quartz (SiO2)

Industrial Slag

Anthropogenic Vitreous Slag

Green Opal or Yellow Opal

Hydrated Silica (SiO2·nH2O)

Obsidian

Volcanic glass (SiO2 + impurities)

Diamond (in a jewelry setting)

Cubic Carbon (C)

Tumbled milky quartz

Quartz (SiO₂), cryptocrystalline-to-massive variety

Brick

Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)

Multi-stone gemstone ring

Likely faceted blue topaz or synthetic blue stone with clear stones, possibly cubic zirconia or diamond; metal setting appears silver-colored alloy

Dyed Quartz (imitating Emerald/Green Quartz)

Silicon Dioxide (SiO2) with artificial pigment

Polished brown stone or bead

Unidentified; possibly polished jasper, agate, or iron-rich quartzite

White marble tile

Calcite-rich marble (CaCO₃)

Metal Chain (Likely Steel or a Steel Alloy)

Steel (primarily iron and carbon); specific alloy unknown

Chert (Arrowhead/Tool variety)

Microcrystalline Quartz (SiO2)

Clear faceted gemstone, likely quartz (rock crystal)

Quartz, silicon dioxide (SiO₂); visual identification is uncertain because the stone is heavily faceted and photographed with flash

Tumbled magnesite

Magnesite (MgCO₃), likely compact or veined magnesite

Drill core, likely weathered granite or granodiorite

Granite–granodiorite core; chiefly quartz, feldspar, and biotite/hornblende

Black Obsidian

Volcanic Glass (SiO2 + impurities)

Gold-colored gemstone ring, likely citrine or glass imitation

Indeterminate from image; possible quartz (SiO₂) or yellow glass set in gold-colored metal

Likely tumbled green stone (possibly serpentine or green aventurine)

Indeterminate from image; candidates include serpentine-group minerals or quartz-rich green aventurine

Chert (Flint / Jasper variant)

Microcrystalline Quartz (SiO2)

Tumbled pale limestone or calcite-rich stone

Limestone, chiefly calcite (CaCO₃); exact identification is uncertain from the photograph

Flint / Chert Pebble

Microcrystalline Quartz (SiO2)

Tumbled Clear Quartz/Rock Crystal

Silicon Dioxide (SiO2)

Pearl

Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3

Likely tumbled jasper or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions

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).