Gemstone

Amethyst

Quartz (Silicon Dioxide, SiO2 with iron impurities)

Turquoise (likely stabilized or simulated Howlite)

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)

Pearl

Calcium Carbonate (CaCO3) with Conchiolin

Rhodochrosite

Manganese carbonate (MnCO3)

Sunstone

Plagioclase Feldspar (Na,Ca)(Si,Al)4O8

Carnelian

Silicon dioxide (SiO2)

Diamond ring

Diamond (crystalline carbon, C)

Tahitian black pearl strand

Cultured pearl; aragonite (CaCO₃) nacre

Blue sapphire ring

Corundum, aluminum oxide (Al₂O₃), blue variety colored mainly by iron and titanium

Precious Coral (Red Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

Pearl

Aragonite and Calcite (CaCO3) with Conchiolin

Citrine

Silicon Dioxide (SiO2)

Orthoclase Feldspar

K(AlSi3O8)

Amethyst

Silicon dioxide (SiO2) with iron impurities

Colorless faceted gemstone, likely cubic zirconia

Cubic zirconia (synthetic ZrO₂), possibly glass or white sapphire

Blue cabochon gemstone ring

Uncertain; likely blue sapphire (corundum, Al₂O₃), blue topaz, or synthetic glass/spinel

Red Jasper with Quartz Veins

SiO2 (Silicon Dioxide with Iron Oxide inclusions)

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

Faceted pale-green gemstone, likely prasiolite or green quartz

Quartz (SiO₂), likely prasiolite; identification is uncertain from the photograph

Cat's Eye Chrysoberyl

Chrysoberyl (BeAl2O4)

Garnet

Silicate mineral group (e.g., Almandine, Fe3Al2(SiO4)3)

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Garnet

Almandine-Pyrope group, X3Y2(SiO4)3

Quartz

Silicon Dioxide (SiO2)

Garnet

Almandine Garnet (Fe3Al2(SiO4)3)

Beaded gemstone jewelry (likely amethyst, lapis lazuli, and pearl or glass imitation)

Mixed mineral beads; possible quartz (SiO₂) and lazurite-bearing lapis lazuli

Faceted yellow-green gemstone, likely peridot

Olivine, typically forsterite-rich (Mg₂SiO₄)

Bojonegoro Green Agate

SiO2 (Chalcedony variety)

Pink coral and green-stone jewelry

Likely pink coral (calcium carbonate, CaCO₃) set with an unidentified green stone; the image is too indistinct to identify the green material reliably.

Red coral beads (possibly dyed or imitation coral)

Corallium spp. skeleton, composed mainly of calcium carbonate (calcite); exact material cannot be confirmed from the image

Lake Superior Agate

Silicon dioxide (chalcedony), SiO2

Amethyst

Silicon dioxide (Quartz variety, SiO2)

Sunstone

Oligoclase feldspar, (Na,Ca)(Al,Si)4O8

Amethyst Cluster

Silicon Dioxide (SiO2)

Clear Quartz (Faceted) or Cubic Zirconia / Glass imitation

SiO2 (if Quartz), ZrO2 (if Cubic Zirconia)

Libyan Desert Glass

Libyan Desert Glass (Tektite / Impact Glass)

Chalcedony

Cryptocrystalline Quartz (SiO2)

Sunstone

Plagioclase Feldspar (Na,Ca)(Si,Al)4O8

Smoky Quartz

Silicon Dioxide (SiO2)

Smoky Quartz

Silicon Dioxide (SiO2) with aluminum impurities

Banded Agate (specifically Lake Superior Agate style)

Agate (Cryptocrystalline Quartz, SiO2)

Lake Superior Agate

Silicon Dioxide (Chalcedony variety)