Black Pearls are so named for the famous shell that they come from. ‘Pinctada Margaritifera’ or ‘The Black Lipped Mother of Pearl Shell’ occurs naturally in the azure lagoons of Manihiki and Penrhyn where the Cook Island pearl farming operations are based. The only other place in the world where they can be found is French Polynesia.
Famed for their large size and fabulous colour, black pearl shells were actively sought after in the 18th and 19th centuries, as it was in huge demand throughout the world for inlaid furniture and buttons, which almost led to the extinction of the pearl.
By accident, large Black Pearls were found and sent to the aristocracy of Europe to be incorporated into royal jewellery. Over time, it was discovered how to 'farm' the pearls and today, this industry remains a thriving one for these outer islands of the Cooks. These lustrous gems of the sea come in several different colours: black, black/green, black rose and green/gold colours.
While generally falling in the 8mm to 14mm diameter size, those bigger than 13mm are rare and much sought after and the more reflective they are, the more the cost increases. Even the shape of a black pearl can be different, ranging from round to drop to baroque to circle. The perfect round one is more expensive but this too is up to the individuals taste. The majority of pearls are sent overseas for lack of local markets.
However, a few are sent to Rarotonga and sold loose or set as pendants, in rings, in earrings and necklaces. The cultivation of the pearl is a long and tedious process, taking around two years before harvesting.
Young oyster shells (spats) are laid out on trays in the lagoon for two years, at which time they are ready to be seeded. A surgical-like operation is required to insert the nucleus and a piece of donor mantle tissue into the gonad of the oyster.
The nucleus is made of mussel shell from the Mississippi and Missouri rivers in the USA. The oyster does the rest. It uses the donor tissue to coat the nucleus. When harvested, the shell can be reused up to 3 times.
The farming industry, which began in earnest in 1997, was decimated by a hurricane in the same year, but since then has recovered and continues to rapidly expand, second only to Tahiti in its export numbers.