Synthetic (Man Made Material Mimicking Natural Stone)

Granite

Intrusive Felsic Igneous Rock (primarily Quartz and Feldspar)

Dyed Agate Geode

Silicon Dioxide (SiO2) with artificial pigment

Crackle Glass (Simulated Gemstone)

Amorphous Solid (SiO2)

Diamond (or Diamond Simulant)

Carbon (C)

Tumbled amethyst

Amethyst, purple quartz (SiO₂)

Raw ruby (likely corundum)

Corundum, Al₂O₃; red color caused mainly by chromium

Star ruby cabochon ring

Corundum, Al₂O₃ (ruby variety), displaying asterism

Diamond (in Jewelry Setting)

Carbon (C)

Aventurine

Aventurine Quartz (SiO2 with inclusions of Fuchsite)

Colorless faceted gemstones, likely quartz (rock crystal)

Quartz, silicon dioxide (SiO₂), trigonal crystal system

Cubic Zirconia

Zirconium dioxide (ZrO2)

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Dyed turquoise-colored lava stone beads

Vesicular basalt (scoria), commonly sold as dyed lava rock

Green Slag Glass

Cullet (Amorphous Silicon Dioxide with impurities)

Multicolor quartz bead bracelet

Quartz (silicon dioxide, SiO₂); bead colors may be from different varieties or treated quartz

Ruby

Corundum (Al2O3 with Chromium traces)

Emerald

Beryl (Be3Al2(SiO3)6) with trace Chromium/Vanadium

Black-and-white agate or onyx bead necklace

Variegated chalcedony (microcrystalline SiO₂), possibly black-and-white banded agate; some black beads may be dyed chalcedony or hematite

Likely iron-rich rock or weathered metallic mineral fragment

Uncertain; possibly limonite/goethite or iron-bearing slag

Diamond

Carbon (C)

Diamond Druzy (Crystalline Diamond)

Carbon (C)

Diamond

Carbon (C)

Tumbled iron-rich stone, likely hematite-bearing jasper

Jasper (microcrystalline quartz, SiO₂) with iron oxides, chiefly hematite/goethite

Diamond

Carbon (C)

Polished black stone carving, likely soapstone/steatite

Steatite (massive talc), Mg₃Si₄O₁₀(OH)₂; exact material cannot be confirmed from the image

Black onyx or black agate bead bracelet

Microcrystalline quartz, chiefly chalcedony (SiO₂); commonly sold as black onyx, sometimes dyed black agate

Amethyst ring

Amethyst, purple quartz (SiO₂), likely set with diamond or other accent stones

Champagne topaz (likely)

Topaz, Al₂SiO₄(F,OH)₂

Ruby / Red Corundum

Al2O3 (Aluminum Oxide with Chromium trace)

Diamond (as set in a metal alloy ring)

Diamond (Pure Carbon, C)

Ruby (Corundum)

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Cubic Zirconia (Simulated Diamond)

Zirconium dioxide (ZrO2)

Sandstone (Pebble)

Sandstone (arenite, arkose, wacke depending on composition)

Polished greenstone/serpentine pebble (probable)

Serpentinite, dominated by serpentine-group minerals (lizardite/chrysotile); possible accessory olivine or chlorite

Chert (possibly a worked stone flake)

Microcrystalline quartz, SiO₂

Diamond (in jewelry setting)

Adamantine Carbon (C)

Unidentified gray metallic object

Not determinable from the image; likely a metal screw or manufactured fastener rather than geological material

Sandstone

Clastic sedimentary rock (Quartz arenite/Arkose)

Colorless faceted gemstone (most likely synthetic cubic zirconia)

Cubic zirconia, ZrO₂ (likely synthetic); natural alternatives include quartz or diamond

Blue gemstone bead bracelet, likely lapis lazuli or dyed stone

Uncertain from image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or dyed quartz/glass imitation

Dyed Agate Slice

Silicon Dioxide (SiO2) with artificial dyes

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)