The black-lipped mother of pearl shell Pinctada margaritifera is a native of the South Pacific and thrives in the clear, unpolluted waters of the lagoons of the Northern Cook islands of Manihiki and Penrhyn . The Cook Islands has built a new and thriving industry out of this interest in the black pearl. The cyclone in Manihiki of November 1997 was a serious setback but the pearl companies have begun the process of reconstruction.
Black pearls derive their lustrous color from the greyish-black nacre of the oyster shell.
There are many different shades of black. Color is not usually a factor in determining price. Growing pearls is a highly skilled process. First, the oyster is collected and a trained technician puts a nucleus into the shell as well as a piece of mantle from a donor shell. The nucleus is a tiny sphere of crushed Mississippi freshwater clam specially farmed for the purpose.