Man Made (Synthetic Rock)

Painted River Rock

Painted Quartzite or Smooth Siltstone

Pearls (likely freshwater cultured pearls)

Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin

Black tumbled stone, possibly obsidian

Obsidian (volcanic glass; predominantly SiO₂), identification uncertain from image

Rounded graywacke or sandstone cobble

Lithified clastic sandstone; likely quartz–feldspar–lithic grain aggregate in a silica or calcite matrix

Rock Crystal (Clear Quartz)

Silicon dioxide (SiO2)

Painted Rock

Weathered Sedimentary Rock (Painted)

Fluorite (Polished Point/Tower)

Calcium Fluoride (CaF2)

Sea Glass

Amorphous silicon dioxide (SiO2) - Man-made glass tumbled by nature

Green glass cabochon or tumbled stone

Indeterminate; likely man-made glass, possibly aventurine glass rather than a natural mineral

Blue Goldstone

Man-made glass with suspended copper, cobalt, or manganese particles

Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Concrete with Aggregate

Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)

Ferrochrome Slag

Anthropogenic slag (Fe-Cr alloy waste)

Blue-dyed tumbled quartz or glass imitation

Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image

Blue Glass or Slag Glass

Amorphous Silica (Anthropogenic Glass)

Faceted Clear Quartz or Diamond Simulant

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

Black glassy fragment, likely obsidian or industrial glass

Volcanic glass (obsidian), chiefly amorphous SiO₂; identification uncertain from image

Blue opalite (often sold as synthetic opal)

Opalite glass; amorphous hydrated silica if natural opal (SiO₂·nH₂O)

Blue obsidian-like volcanic glass

Volcanic glass, chiefly silica-rich amorphous material (composition uncertain)

Milky quartz (likely quartz crystal fragment)

Quartz, silicon dioxide (SiO₂)

Cut purple gemstone, likely synthetic cubic zirconia or glass

Undetermined; possible cubic zirconia (ZrO₂)

Blue goldstone beads

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

Terrazzo (with Marble and Granite fragments)

Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates

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Sea Glass (White/Clear)

Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO

Quartz crystal (likely clear quartz)

Quartz, silicon dioxide (SiO₂)

Polished black stone, likely black obsidian

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

Pink Tumbled Quartz (Dyed)

Silicon Dioxide (SiO2)

Dyed Crackle Quartz (Green)

Quenching-treated Quartz (Silicon Dioxide, SiO2)

Pyrite Concretion (Grapestone)

Iron Sulfide (FeS2) Concretion

Tumbled gray stone, likely quartz-rich pebble

Probable microcrystalline quartz/chalcedony (SiO₂), possibly gray jasper or quartzite

Slag Glass

SiO2 (Silicon Dioxide) with impurities

Black Obsidian

Amorphous volcanic glass (SiO2 + impurities)

Green sea glass or tumbled green quartz (uncertain)

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

Opalite

Synthetic glass (Opalite simulant)

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

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

Polished white calcite sphere (identification tentative)

Calcite, CaCO₃

Sea Glass

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

Aura Quartz (Titanium/Gold coated)

Silicon Dioxide (SiO2) with metallic vapor deposition

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)