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Figure 1. Chalcedony petrified tree fern is carved as an ornamental gem material. This 60 × 40 mm dragon carving has a uniform texture and bright color. Photo by Hai-Long Wang.

A Unique Petrified Tree Fern from Northeast China

Ying Yan, Xiao-Yan Yu, Han-Yue Xu, and Zhi-Rong Xie, January 26, 2024

Documents the gemological properties, chemical composition, and appearance of petrified tree fern discovered in northeast China.

Figure 1. This 1.27 ct white semi-baroque pearl exhibited a typical platy structure when examined under magnification. Photo by Lhapsin Nillapat.

Tubular Feature in a Natural Pearl

Ravenya Atchalak and Emiko Yazawa, January 26, 2024

Investigation of a tubular feature in a natural pearl reveals evidence of parasitic activity.

Figure 1. This antique Indian-style headdress is decorated with handwoven light cream and cream-colored seed pearls. Photo by Gaurav Bera.

Seed Pearls in an Antique Indian-Style Headdress

Roxane Bhot Jain, Jayesh Surve, Abeer Al-Alawi, and Chunhui Zhou, January 26, 2024

GIA’s Mumbai laboratory analyzes seed pearls decorating an Indian-style headdress.

Figure 1. <em>Pinctada radiata</em> shell with a natural blister pearl measuring approximately 11.39 × 9.31 × 8.69 mm. Photo by Gaurav Bera.

An Unusual Partially Non-Nacreous Pinctada radiata Natural Blister Pearl

Abeer Al-Alawi, Lubna Sahani, Karan Rajguru, and Roxane Bhot Jain, January 26, 2024

A large Pinctada radiata natural blister pearl displays a unique reaction under long-wave ultraviolet light.

Figure 1. Various negative crystals in pink sapphire from Sri Lanka (A, enlarged in B) and fingerprints in blue sapphire from Burma (C, enlarged in D). Image B shows bubbles in flat negative crystals, and the center negative crystal in D has a bubble. Photomicrographs by Momo Matsumura (A and B) and Shunsuke Nagai (C and D); fields of view 4.05 mm (A), 8.15 mm (B), 8.47 mm (C), and 1.71 mm (D).

FTIR Identification of Carbon Dioxide Fluids in Sapphire

Kazuko Saruwatari, January 26, 2024

FTIR spectroscopy shows that the existence of carbon dioxide gas bubbles in a negative crystal in sapphire is no longer proof of the absence of heat treatment.

Figure 1. A rare 1.04 ct semitransparent thomsonite measuring 7.53 × 6.15 × 4.67 mm. Photo by Adriana Robinson.

Rare Faceted Thomsonite

Michaela Damba, January 26, 2024

A colorless semitransparent thomsonite is examined in the Carlsbad laboratory.

Eight European natural freshwater pearls from Margaritifera margaritifera mussels.

Natural Freshwater Pearls from Europe: Russia, Scotland, and Germany

Artitaya Homkrajae, Ziyin Sun, Elisabeth Strack, and Sally Chan Shih, September 3, 2021

Analysis of eight European freshwater pearls of known provenance gives pearl specialists the opportunity to add greatly to GIA’s identification database.

Freshwater bead cultured pearl necklace.

Vaterite Found on a Strand of Freshwater Cultured Pearls

Sally Chan Shih, January 28, 2022

An unusual formation of vaterite was identified on the surface of numerous freshwater cultured pearls throughout a single strand.

This 9.885 kg specimen of aquamarine on albite with a quartz cathedral center, measuring 31 × 23 × 28 cm, is from Pakistan’s Shigar Valley. Courtesy of GIA Museum, collection no. 43068. Photo by Robert Weldon.

Micro-Features of Beryl

Nathan Renfro, Tyler Smith, John I. Koivula, Shane F. McClure, Kevin Schumacher, and James E. Shigley, January 26, 2024

Provides a visual guide to the internal features of different varieties of beryl.

An Early Byzantine Engraved Almandine from the Garibpet Deposit, Telangana State, India: Evidence for Garnet Trade Along the Ancient Maritime Silk Road

H. Albert Gilg, Karl Schmetzer, and Ulrich Schüssler, August 6, 2018

Analyzes the chemical composition and inclusion characteristics of this ancient artifact.

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