Winter 2022 G&G Available Now

Brooke Goedert

January 25, 2023

The Winter issue features three studies on identifying treatments in colored gemstones—ruby, feldspar, and turquoise—and introduces us to an inspirational artist and pioneer in the jewelry industry. In addition to the four feature articles and our quarterly sections, we see the return of Colored Stones Unearthed.

A CANARY IN THE RUBY MINE: LOW-TEMPERATURE HEAT TREATMENT EXPERIMENTS ON BURMESE RUBY

E. Billie Hughes and Wim Vertriest conduct low-temperature heating experiments on Burmese ruby. The appearance of inclusions at each heating step, coupled with spectroscopic analysis, provides evidence of this treatment. Particular solid inclusions proved sensitive to low-temperature heating.

FLUORESCENCE CHARACTERISTICS OF TWO COPPER-DIFFUSED PLAGIOCLASE FELDSPARS: LABRADORITE AND ANDESINE

For this study, Qingchao Zhou and fellow researchers treated colorless labradorite and light yellow andesine with copper diffusion to mimic the color of natural labradorite sunstone. They discovered that fluorescence emission characteristics under 320 nm excitation can potentially help identify copper diffusion treatment in a material that has been a subject of controversy for decades.

COMPOSITION AND SPECTRAL CHARACTERISTICS OF PORCELAIN-TREATED TURQUOISE

A team led by Liying Huang uses a combination of low specific gravity, strong luster, high silica content, and surface features to effectively identify the novel “porcelain” treatment technique. This treatment method improves the luster and color of low- to medium-quality turquoise to meet the demand for scarcer high-quality natural turquoise in the Chinese market.

NEVER STOP INNOVATING: GEM ARTIST CHI HUYNH

Tao Hsu and coauthors visit Chi Huynh, founder and owner of Galatea: Jewelry by Artist, who shares his experiences and passion for jewelry-making innovations. Carved pearls, gem bead cultured pearls, and two-way shape-memory jewelry are but a few of the groundbreaking jewelry design concepts he employs in his finished pieces.

LAB NOTES

GIA’s global laboratory staff present their latest findings in the Lab Notes section, including a unique chrysoberyl displaying four-rayed asterism, the largest cat’s-eye emerald examined by GIA to date, and the identification of two non-nacreous bead cultured pearls from Pinctada margaritifera.

MICRO-WORLD

The Micro-World section, dedicated to the inner world of gemstones, features unusual “horsetail” and columnar inclusions in demantoid, a bluish green omphacite crystal in colored diamond, and aegirine inclusions in poudretteite from a new deposit in Mogok.

COLORED STONES UNEARTHED

Colored Stones Unearthed returns to examine gem minerals that form in magmatic environments, such as diamond, garnet, spinel, and corundum. Through these gems, gemologists gain insights into the generation of magmas within the earth, their transport to the surface, and modes of volcanic processes after eruption.

GEM NEWS INTERNATIONAL

Finally, GNI’s global contributors report on a variety of topics, including an extremely rare hellandite inclusion in ruby from Mogok; the identification of natural, reconstructed, and imitation Burmese root amber; and a roundup of the fall 2022 auction highlights, which had several surprising twists.