Not A Rock (Synthetic Material)

Green cabochon gemstone, possibly peridot

Uncertain from the photo; possible gem-quality olivine, (Mg,Fe)₂SiO₄

Emerald in Matrix

Beryl (Be3Al2Si6O18) with trace amounts of Chromium/Vanadium

Lapis Lazuli

Lazurite-dominant metamorphic rock, Na8[Al6Si6O24]n(S,Cl,SO4,OH)2

Black spinel bead bracelet

Spinel (magnesium aluminate), MgAl₂O₄

Tumbled amethyst

Amethyst, purple quartz (SiO₂)

Tiger’s eye

Quartz (SiO₂), fibrous pseudomorph after crocidolite

Turquoise

Turquoise, hydrated copper–aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O

Pearls

Pearl: biomineralized aragonite (CaCO₃) and conchiolin

Synthetic Resin / Plastic Figurine

Synthetic Polymer (Copolymer of Polyethylene or Resin)

Opalite

Man-made Opalized Glass (Synthetic Glass)

Opalite

Man-made Glass (Synthetic Opalized Glass)

Red coral chip bracelet

Corallium spp.; skeleton composed primarily of calcium carbonate (aragonite)

Tumbled red jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Weathered granitic rock fragment

Granite, likely quartz–feldspar–biotite aggregate

Opal ring

Precious opal, hydrated amorphous silica (SiO₂·nH₂O), set in a metal ring

Iridescent polished/tumbled stone (likely coated quartz or glassy synthetic material)

Indeterminate; possibly quartz (SiO₂) with an artificial iridescent coating

Silicon Carbide

Silicon Carbide (Moissanite / Carborundum), SiC

Red coral beads

Precious coral, commonly Corallium rubrum (calcium-carbonate skeleton)

Green cabochon gemstone, likely glass-filled or synthetic emerald imitation

Uncertain; possible synthetic emerald (beryl, Be₃Al₂Si₆O₁₈) or green glass

Peridot gemstone pendant

Olivine, gem-quality forsteritic olivine (approximately (Mg,Fe)₂SiO₄)

Opal ring (likely precious opal)

Hydrated amorphous silica, SiO₂·nH₂O; the pictured stone may be natural opal or a lab-created/imitation opal

Blue Goldstone

Aventurine Glass (SiO2 with Co and metallic inclusions)

Marine gastropod shell

Calcium-carbonate shell, primarily aragonite; species cannot be determined from the image

Blue-stone and diamond ring

Blue stone is possibly blue sapphire (corundum, Al₂O₃); surrounding stones appear to be diamonds (carbon, C).

Likely rough amber

Amber (fossilized tree resin; composition varies, commonly dominated by polymerized terpenoids)

Man-made Jewelry (Metal and Glass/Plastic)

Synthetic Alloy and Amorphous Solid (SiO2/Polymer)

Silicon Carbide (Carborundum)

Silicon Carbide (SiC)

Carborundum (Silicon Carbide)

Silicon Carbide (SiC)

Blue glass-like cabochon, likely dyed or synthetic material

Uncertain; possibly dyed chalcedony, synthetic spinel, or blue glass

Diamond ring

Diamond, crystalline carbon (C), likely colorless or near-colorless brilliant-cut stones set in gold

Cherry Quartz with Rose Quartz

Crystalline Quartz (SiO2) with glass-based synthetic components

Pink quartz (likely rose quartz)

Quartz, silicon dioxide (SiO₂), likely rose quartz; possibly lab-created or treated

Green faceted gemstone, likely tsavorite garnet

Tsavorite: green grossular garnet, Ca₃Al₂(SiO₄)₃

Quartzite (Engineered Stone)

Silicon Dioxide (SiO2) based synthetic composite

Blue Goldstone

Aventurine Glass (SiO2 with Cobalt/Copper inclusions)

Goldstone

Aventurine glass (Synthetic glass with copper inclusions)

Lapis Lazuli (Low Grade)

Lazurite-rich metamorphic rock ((Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2)

Bauxite

Bauxite (Mixture of Hydrous Aluminum Oxides)

Raw ruby (likely corundum)

Corundum, Al₂O₃; red color caused mainly by chromium

Faceted citrine-colored gemstone

Likely citrine (quartz, SiO₂); possibly yellow glass or synthetic gem

Asphalt (Bituminous Concrete)

Bituminous Concrete / Pavement

Red corundum gemstone (likely synthetic ruby)

Ruby: corundum, aluminum oxide (Al₂O₃), chromium-colored; likely lab-grown material