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Figure 1. A strand of baroque-shaped freshwater bead cultured pearls shown with two <em>Tridacna</em>-species mollusk shells from GIA’s shell reference collection. Each sample weighs approximately 20 ct, ranging from 16.73 × 12.58 × 12.49 mm to 18.98 × 13.53 × 13.43 mm. Photo by Nuttapol Kitdee.

Saltwater Clamshell Beads (Tridacna Species) Used in Freshwater Cultured Pearls

Kwanreun Lawanwong, August 4, 2023

A report from GIA’s Bangkok laboratory on freshwater bead cultured pearls with saltwater bead nuclei.

Figure 1. The cream-colored pearl weighing 0.23 ct and measuring 3.20 × 3.12 mm, shown against the anterior of a <em>Pinctada radiata</em> mollusk. Photo by Nuttapol Kitdee.

An Unusual Metallic Core in a Natural Pinctada radiata Pearl from Kuwait

Ravenya Atchalak, Kwanreun Lawanwong, Emiko Yazawa, and Abeer Al-Alawi, August 4, 2023

Examination of natural pearls from Kuwait reveals one with a suspected metal oxide at the core.

Figure 1. The white and cream non-nacreous pearl weighing 0.29 ct and measuring 3.75 × 3.55 mm. Photo by Gaurav Bera.

Calcite Present in a Pearl from Pinctada maculata

Anukul J. Belanke, Roxane Bhot Jain, Nishka Vaz, and Abeer Al-Alawi, August 4, 2023

Examination of a Pinctada maculata pearl reveals an interesting columnar calcite surface structure.

A 4.77 ct near-round white Tridacninae pearl exhibited an attractive sheen-like flame structure in a pattern resembling an eye when viewed in certain directions under a single white light source. Photomicrograph by Ravenya Atchalak; field of view 7.20 mm.

An “Eye” on a Tridacninae Pearl

Ravenya Atchalak, August 4, 2023

A Tridacninae pearl exhibits a flame structure resembling an eye.

Four non-bead cultured pearls (samples 1–4, left to right) weighing 0.22 to 4.84 ct. Photo by Gaurav Bera.

Fine Linear Structures in Non-Bead Cultured Pearls

Gauri Sarvankar, Abeer Al-Alawi, Karan Rajguru, and Roxane Bhot Jain, August 4, 2023

Analysis of internal structures in non-bead cultured pearls submitted to GIA’s Mumbai laboratory.

Figure 1. The large round bead cultured pearl weighing 54.96 ct and measuring 19.90 × 19.53 mm. Photo by Gaurav Bera.

A Fascinating Large South Sea Bead Cultured Pearl

Roxane Bhot Jain, Abeer Al-Alawi, and Chunhui Zhou, August 4, 2023

An exceptionally large South Sea bead cultured pearl is examined at GIA’s Mumbai laboratory.

Figure 1. The Lord Hanumana pearl (left, 33.70 × 32.98 × 24.64 mm) and the Lord Ganesha pearl (right, 10.59 × 10.21 × 9.18 mm). Photo by Gaurav Bera.

Two Pearls of Indian Cultural Significance

Nishka Vaz, Rajesh Patel, and Abeer Al-Alawi, August 4, 2023

Two pearls representing Indian deities were recently examined in the Mumbai laboratory.

Article

Summer 2023 G&G Available Now

Erica Zaidman, August 4, 2023

An overview of the Summer 2023 Gems & Gemology content.

Figure 1. Mammoth ivory carving with part of the brown surface retained to depict the characters. Courtesy of Duo Wang.

Origins of Color in Brown Mammoth Ivory

Zhaoying Huang, Tao Chen, Jinyu Zheng, Duo Wang, and Xing Xu, August 4, 2023

Investigates the mineral and chemical compositions and surface morphology characteristics of brown mammoth ivory to identify the origins of its brown color.

Figure 1. The 169.05 ct filled pearl, viewed from its face (left) and base (right). Note the indented feature on the base through which the filler material was inserted prior to plugging. Photos by Gaurav Bera.

A Partially Hollow Natural Blister Pearl Filled with Foreign Materials

Roxane Bhot Jain, Abeer Alalawi, Nicholas Sturman, and Chunhui Zhou, January 25, 2023

A very large baroque white pearl is further examined in the Mumbai laboratory due to its suspicious heft.

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