Mineral (Treated)

Citrine or Yellow Quartz

Quartz (SiO2) with iron impurities

Tumbled yellow quartz, likely citrine or iron-stained quartz

Quartz (SiO₂), possibly citrine variety

Yellow Quartz (Citrine Quartz)

Silicon Dioxide (SiO2)

Emerald and Diamond (Jewelry Setting)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities) and Carbon (C)

Tumbled yellow quartz (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂), yellow coloration from iron impurities

Chalcopyrite (Peacock Ore)

Copper Iron Sulfide (CuFeS2)

Tumbled pink quartz, likely dyed

Quartz (silicon dioxide, SiO₂), probably artificially colored chalcedony or milky quartz

Citrine

Silicon Dioxide (SiO2) - Macrocrystalline Quartz variety

Dyed Alum or Dyed Quartz (Ornamental Crystal)

Silicon Dioxide (SiO2) or Potassium Alum [KAl(SO4)2·12H2O]

Blue Topaz

Aluminum Silicate Fluoride Hydroxide - Al2SiO4(F,OH)2

Citrine

Silicon Dioxide (SiO₂)

Emerald (green gemstone) pendant

Emerald, green variety of beryl (Be₃Al₂Si₆O₁₈); stones appear to be faceted and set in jewelry

Howlite (polished/tumbled)

Howlite — hydrated calcium borosilicate, Ca₂B₅SiO₉(OH)₅

Spessartine Garnet

Manganese aluminum silicate (Mn2+3Al2(SiO4)3)

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine/Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Quartz (Citrine or Iron-Stained)

Silicon Dioxide (SiO2)

Tumbled quartz (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

Citrine

Silicon Dioxide (SiO2)

Red-orange sunstone (likely aventurine feldspar) bead bracelet

Feldspar, commonly oligoclase or labradorite with copper inclusions; composition varies by source

Yellow Quartz

Silicon Dioxide (SiO2)

Citrine

Silicon Dioxide (SiO2)

Citrine Quartz

Crystalline Quartz (SiO2 with iron impurities)

Dzi Bead (Agate Bead)

Cryptocrystalline Quartz (SiO2) - Chalcedony/Agate

Citrine

Citrine (Silicon Dioxide, SiO2)

Red corundum (ruby) crystal fragment

Corundum, Al₂O₃; ruby is red corundum colored mainly by chromium

Citrine

Silicon dioxide (SiO2) - yellow quartz variety

Polished carnelian agate

Carnelian, a translucent orange variety of chalcedony (microcrystalline quartz, SiO₂)

Citrine

Silicon Dioxide (SiO2) with iron impurities

Amethyst crystal

Amethyst, purple variety of quartz (SiO₂), trigonal crystal system

Rose quartz cabochon

Quartz, SiO₂ (rose quartz; trigonal crystal system)

Peacock Ore

Bornite (Cu5FeS4) or Acid-Treated Chalcopyrite (CuFeS2)

Yellow quartz fragment (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂), trigonal crystal system

Polished yellow gemstone fragments, likely citrine or yellow sapphire

Uncertain from image; likely quartz (SiO₂) if citrine, or corundum (Al₂O₃) if yellow sapphire

Citrine

Silicon Dioxide (SiO2) with iron impurities

Tumbled yellow quartz, possibly citrine

Quartz (SiO₂), likely iron-colored citrine or pale golden chalcedony

Black Onyx

Silicon Dioxide (SiO2) with parallel banding

Black Onyx

Chalcedony (Silicon Dioxide, SiO2)

Citrine (Heat-Treated Amethyst)

Quartz (SiO2)

Blue glassy gemstone-like specimen

Indeterminate; possibly dyed or treated turquoise, blue apatite, or man-made glass

Quartz (Citrine or Iron-Stained variety)

Silicon Dioxide (SiO2)

Bornite (Peacock Ore) / Acid-treated Chalcopyrite

Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2)