Mineraloid (Synthetic)

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Limonite (Iron Ore)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Small blue cut gemstone, possibly synthetic spinel or glass; species cannot be determined from the photo

Undetermined; blue synthetic spinel (MgAl₂O₄) is one possibility

Goldstone

Aventurine Glass (Man-made)

Colorless faceted gemstone, likely cubic zirconia

Synthetic cubic zirconia (ZrO₂), tentative; possibly diamond or synthetic moissanite

Faceted purple-blue beads, likely synthetic glass or treated gemstone

Indeterminate; possible synthetic corundum, synthetic spinel, or dyed quartz (SiO₂)

Red cabochon gemstone ring (likely glass or synthetic stone)

Undetermined; the image does not establish a natural mineral identity

Blue gemstone ring, likely blue topaz or synthetic blue spinel

Likely topaz (Al₂SiO₄(F,OH)₂) or synthetic spinel (MgAl₂O₄); identification is uncertain from the image

Amethyst quartz cluster

Quartz, SiO₂; purple variety amethyst

Shungite

Carbon-rich mineraloid (Amorphous carbon)

Shungite

Shungite (carbon-rich Precambrian mineraloid)

Pearl (Biogenic Mineraloid)

Calcium carbonate (Aragonite) and Conchiolin, CaCO3

Opalite

Synthetic Glass (Simulated Opal)

Diamond (or Diamond Simulant)

C (Carbon) or synthetic equivalent

Opalite

Synthetic glass / Opalized glass

Opalite

Synthetic Glass (Simulated Opal)

Opalite Egg

Synthetic Glass (Simulated Opal)

Opalite

Synthetic Glass (SiO2 + impurities)

Opalite

Synthetic Silicon Dioxide (SiO2)

Green Opal

Hydrated Silica (SiO2·nH2O)

Precious Opal

Hydrated Silica (SiO2·nH2O)

Limonite/Ironstone

Limonite (FeO(OH)·nH2O)

Pearl (Biogenic Mineraloid)

Calcium carbonate (CaCO3) primarily as Aragonite

Luminous Stone (Glow-in-the-dark Synthetic/Man-made Stone)

Strontium Aluminate tinted glass or resin (Crystalline silicate/oxide mix)

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurity)

Limonite (Iron Ore)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Likely obsidian (possibly tektite or slag glass)

Volcanic glass; primarily SiO₂, noncrystalline

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Jet

Lignite (Anthracite-grade compact coal)

Obsidian

Volcanic Glass (SiO2)

Man-made Synthetic Material (Not a rock or mineral)

Polyester (Polyethylene terephthalate) / Faux Fur

Man-made Synthetic Material (Plastic/Composite)

Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)

Green faceted gemstone, likely synthetic glass or peridot

Indeterminate from image; possible peridot (olivine, (Mg,Fe)₂SiO₄) or green synthetic glass

Blue Sapphire (likely costume glass imitation)

Corundum (Al2O3) with iron/titanium impurities

Faceted transparent gemstone pendant

Likely cubic zirconia (zirconium dioxide, ZrO₂); possibly diamond or synthetic moissanite

Painted Rock

Weathered Sedimentary Rock (Painted)

Painted River Rock

Painted Quartzite or Smooth Siltstone

Costume Jewelry with Synthetic Gemstones

Synthetic Cubic Zirconia and Glass (SiO2 / ZrO2)

Faceted gemstone in a jewelry setting

Indeterminate from image; likely quartz, cubic zirconia, or another transparent faceted stone

Pink faceted gemstone, likely synthetic or treated quartz

Quartz, silicon dioxide (SiO₂); exact identity cannot be confirmed from the image

Obsidian (black volcanic glass), possibly slag or basalt

Obsidian; chiefly amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition

Opal

Hydrated Silica (SiO2·nH2O)