GIA research expedition nets 700-plus natural pearls

Bangkok--Gemological Institute of America (GIA) researchers from Thailand, along with representatives from the Paspaley Pearling Company, recently conducted an expedition to Australia’s wild pearl oyster beds that resulted in a number of successful natural pearl finds, the two organizations said.

GIA pearl researchers Artitaya Homkrajae and Areeya Manustrong spent 10 days in late September and early October aboard the Paspaley diving ship, MV Marilynne, on an expedition that focused on gathering the shells of Pinctada maxima, the world’s largest species of pearl oysters.

The point of the expedition was to gather samples to further research in differentiating certain saltwater cultured pearls from natural pearls, a major focus for both the GIA and Paspaley Pearling Company.

According to the GIA, prior to this expedition there were few opportunities for gemological laboratories to conduct research on undrilled natural pearls with a known provenance, and the origin would instead be “assumed.”

These new samples now provide them with a unique opportunity to compare what is understood about natural structures with undrilled pearls known to be natural.

During the expedition, the GIA researchers and the representatives from Paspaley discovered and extracted 776 natural pearls from 20,488 large wild oysters.

Many of the pearls were small “seed” pearls, with the most diminutive measuring less than 1 mm in diameter. The largest was a rare pearl measuring 16 mm.

The found pearls and their shells now are located in GIA’s laboratory in Bangkok. The GIA said it will conduct extensive research on the pearls over the next few months, using in-house high resolution real-time microradiography and micro CT imaging, among other testing methods.

Several recent expeditions by the GIA into the waters off the northwest coast of Australia have resulted in a number of finds for the company of both natural and cultured pearls, lending to data that will help the lab establish test criteria for its pearl identification teams.

“Resolving the issues involved in differentiating natural from saltwater non-bead cultured pearls has been a focus of GIA’s research group for some time,” said Kenneth Scarratt, GIA managing director for Southeast Asia, in a statement. “Meeting these challenges and using the results to serve GIA’s public benefit mission is what makes this kind of research so rewarding and important.”