Little Blue Pills Make Bigger, More Lustrous Pearls

When Jeremy Shepherd, the CEO of, saw a strand of what he thought were supremely lustrous, richly hued, and uncommonly large 20 mm Tahitian keshi at Emiko Pearls’ booth at this year’s AGTA Tucson GemFair, he was both intrigued and confused. If they were keshi, they would certainly be among the biggest and most colorful he’d ever seen—the pearls were dark with hints of green and aubergine—but how could keshi pearls (typically non-nucleated pearls that are 100 percent nacre and a by-product of pearl cultivation) be that large and lustrous, he wondered. Ron Greenidge, director of Emiko Pearls in Bellevue, Wash., explained that the pearls were not keshi but bead-nucleated gems that he first saw in 2013. (Greenidge told JCK at LUXURY 2014 that he bought all available strands at the time, which had pearls ranging in size from 15 to 17 mm, and that sold for $8,000 to $15,000 retail.)

After further research, Shepherd learned that the pearls were grown with the help of a little blue pill—just like a certain human medication that induces another type of stimulation—produced by Japanese firm Imai Seikaku. Its patented FNC BIO nuclei uses natural fibronectins (proteins obtained from blood and bone marrow that occur in fluid form as sugars) to enhance cellular adhesion and “effectively make superlative pearl sacs in a shorter time” and “accelerate the formation of pearl layers,” according to the company’s website.

According to Shepherd, the pills “induce even a small young pearl oyster to grow a large pearl sac where an equally large nucleus can be placed,” he explains.

Tahitian pearl farmer Josh Humbert of Kamoka Pearls has been experimenting with the blue pills for about three years at his farm in Tahiti. “They act like an expanding gel and blow up inside the gonad of an oyster and help it to form very large pearl sac,” he explains. And for Tahitians, whose richest colors are commonly found in the smallest sizes because larger pearls are born from mature oysters—which, as they age tend to lose luster, including the ability to produce fine nacre in robust peacock hues—the nuclei are especially intriguing because they permit giant, lustrous material to be made for a fraction of the cost for the benefit of consumers—provided they are properly disclosed at the time of sale.

Inside the oyster, the pills eventually disintegrate as a pearl forms around it, creating a hollow pearl—illegal to export in Tahiti—but there is speculation that these blue pill nuclei gave rise to Edison pearls (large round bead-nucleated freshwaters) and Soufflé pearls, the lightweight lustrous freshwater baroques that entered the jewelry scene five years ago. (Regarding the latter, American experts initially thought they were seeded with mud balls.)

Though Humbert can’t legally sell the second-generation oysters he seeded with the pills, he is hoping for large and lustrous bead-nucleated pearls in the third generation thanks to those enlarged sacs. (The third generation won’t be ready for at least another six to eight months.)

For more information, consult “New developments in cultured pearl production: use of organic and baroque shell nuclei” by Laurent E. Cartier and Michael S. Krzemnicki.