Reports on a visit to a shell nucleus manufacturer and two pearl farms in northern Vietnam, which is emerging as a notable producer.

The Carlsbad laboratory received for examination two dark-colored bead cultured pearls embedded with an electronic device from Jeremy Shepherd, CEO of Pearl Paradise.

An emerald from the Swat Valley manifests its growth in three distinct steps, identifying it as “trapiche-type.”

Epigenetic residue in rock crystal quartz creates a novelty inclusion with the appearance of a fried egg.

Examination of a large black star sapphire reveals filling with both glass and dopping varnish.

An overview of the Fall 2020 Gems & Gemology content.

Testing of a Mogok spinel demonstrates that oil can have a significant impact on clarity.

加利福尼亚州卡尔斯巴德 — 2021 年 1 月 21 日 — 注册参加 GIA 宝石知识周：春姿绽放。本次激动人心的虚拟活动为期四天，带您遨游有色宝石的美丽世界。

Eaton-Magaña S., Breeding C.M., Palke A.C., Homkrajae A., Sun Z.Y., McElhenny G. (2021) Raman and photoluminescence mapping of gem materials. Minerals, Vol. 11, No. 2, Art. 177.

近日，GIA 纽约鉴定所有幸检验了一颗迷人的珍珠，它的故事更加引人入胜，快来一探究竟吧。

Smith E.M., Nestola F., Pasqualetto L., Zorzi F., Seccon L., Wang W. (2021) The new mineral crowningshieldite: A high-temperature NiS polymorph found in a type IIa diamond from the Letseng mine, Lesotho. American Mineralogist, Vol. 106, No. 2, pp. 301-309.

Smith E.M., Ni P., Shirey S.B., Richardson S.H., Wang W., Shahar A. (2021) Heavy iron in large gem diamonds traces deep subduction of serpentinized ocean floor. Science Advances, Vol. 7, eabe 9773

Annotated reading lists compiled on Lazurite (Lapis Lazuli) from Afghanistan and its Artistic Use as a Blue Pigment (Ultramarine)

Ashfold M.N.R., Goss J.P., Green B.L., May P.W., Newton M.E., Peaker C.V. (2020) Nitrogen in diamond. Chemical Reviews, Vol. 120, No. 12, pp. 5745-6794.

Breeding C.M., Eaton-Magaña S., Shigley J.E. (2020) Naturally colored yellow and orange gem diamonds: The nitrogen factor. Gems & Gemology, Vol. 56, No. 2, pp. 194-219.

Diggle P.L., D’Haenens-Johansson U.F.S., Green B.L., Welbourn C.M., Thi T.N.T., Katrusha A., Wang W., Newton M.E. (2020) Decoration of growth sector boundaries with nitrogen vacancy centers in as-grown single-crystal high-pressure high-temperature synthetic diamond. Physical Review Materials. Vol. 4, No. 9, Article 093402.

Dubinsky E.V., Stone-Sundberg J., Emmett J.L. (2020) A quantitative description of the causes of color in corundum. Gems & Gemology, Vol. 56, No. 1, pp. 2-28.

Eaton-Magaña S., McElhenny G., Breeding C.M., Ardon T. (2020) Comparison of gemological and spectroscopic features in type IIa and Ia natural pink diamonds. Diamond and Related Materials, Vol. 105, Article 107784.

Eaton-Magaña S., Ardon T. (2020) Spatial distribution of defects in natural type IIb diamond after irradiation and annealing. Diamond and Related Materials. Vol. 109, Article 108034.

Eaton-Magaña S., Ardon T., Breeding C.M., Shigley J.E. (2020) Natural color D-to-Z diamonds: A crystal clear perspective. Gems & Gemology, Vol. 56, No. 3, pp. 318-335.