Mineral (Treated)

Yellow Quartz (Citrine or Yellow Jasper)

Silicon Dioxide (SiO2)

Yellow Quartz / Citrine Pebble

Silicon Dioxide (SiO2)

Chalcopyrite

CuFeS2 (Copper Iron Sulfide)

Black Onyx

Silicon Dioxide (SiO2)

White Topaz

Al2SiO4(F,OH)2

Peacock Ore

Bornite (Cu5FeS4) or iridescent Chalcopyrite (CuFeS2)

Yellow Quartz

Silicon Dioxide (SiO2)

Prasiolite (Green Quartz)

Silicon Dioxide (SiO2) with iron impurities

Turquoise bead necklace

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

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Dyed and polished turquoise

Turquoise, CuAl₆(PO₄)₄(OH)₈·4H₂O

Blue Sapphire

Corundum (Al2O3) with traces of Iron and Titanium

Polished blue-green glassy slag or coated mineral fragment

Most likely man-made colored glass/slag; exact composition cannot be determined visually

Red Howlite (Dyed)

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5) with Red Dye

Blue metallic mineral specimen, possibly bornite or chalcopyrite

Bornite (Cu₅FeS₄) or chalcopyrite (CuFeS₂); exact identification requires testing

Chalcopyrite

Chalcopyrite (CuFeS2)

Blue-green gemstone ring, likely treated turquoise or synthetic/treated beryl

Indeterminate from image; possibilities include turquoise (CuAl6(PO4)4(OH)8·4H2O), apatite, or treated beryl

Polished carnelian (banded agate)

Chalcedony, microcrystalline quartz (SiO₂), likely iron-stained banded agate

Blue magnesite beads

Magnesite (MgCO₃), likely stabilized or dyed; brown veining may reflect matrix or iron oxides

Pink/red faceted gemstone, likely synthetic ruby or pink sapphire

Corundum, aluminum oxide (Al₂O₃); likely lab-grown or treated material

Mixed mineral and gemstone specimens

Likely amethyst (quartz), malachite, blue calcite or dyed chalcedony, red jasper, and green aventurine/serpentine

Peacock ore (bornite/chalcopyrite), likely treated

Bornite, Cu₅FeS₄, and/or chalcopyrite, CuFeS₂

Black tourmaline bead bracelet

Schorl tourmaline, NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Polished tiger’s-eye

Quartz (SiO₂), chatoyant fibrous variety; commonly golden-brown tiger’s-eye

Tumbled sodalite beads

Sodalite, Na8(Al6Si6O24)Cl2, commonly with minor white calcite or nepheline

Yellow quartz crystal (likely citrine)

Quartz, silicon dioxide (SiO₂), iron-colored variety commonly called citrine

Heat-Treated Citrine (Amethyst)

Silicon Dioxide (SiO2) with iron impurities

Gemstone ring (stone appears pale yellow, possibly citrine or glass imitation)

Undetermined; possible quartz variety citrine (SiO₂)

Black cabochon gemstone, likely onyx or agate

Likely chalcedony (microcrystalline quartz, SiO₂); exact identification is not possible from the photo

Citrine

Silicon dioxide (SiO2)

Tiger's Eye (Multicolor/Variegated)

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxides)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Tumbled turquoise

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

Tumbled smoky quartz

Quartz (SiO₂), brown smoky variety

Tumbled chrysocolla beads

Chrysocolla, hydrated copper-aluminum silicate (approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O), commonly mixed with malachite or quartz

Amethyst

Amethyst is a variety of Quartz (SiO₂)

Polished picture jasper (likely a jasper-and-chalcedony slab)

Microcrystalline quartz, SiO₂; jasper is an opaque variety of chalcedony

Polished amber-colored quartz (likely citrine or iron-stained quartz)

Quartz, SiO₂; yellow color from trace iron and/or inclusions

Polished agate/geode slice

Chalcedony (microcrystalline quartz, SiO₂), likely agate with an altered druzy/quartz interior

Tiger's Eye

Silicon Dioxide (SiO2) - Pseudomorph of Quartz after Crocidolite

Tumbled Amethyst

Silicon Dioxide (SiO2) with iron impurities

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)