The pearl industry in Australia is focused across the northern states and territories, with Broome generally acknowledged as the pearl capital of Australia. Traditionally the industry is focused on the production of South Sea pearls from the Pinctada maxima oyster, although there is an emerging black pearl industry from Pinctada margaritifera oysters, and Akoya pearls from Pinctada fucata martensi oysters.
The pearl cultivation process begins with the careful collection of wild pearl oysters from the sea floor by a team of divers. These oysters are then ‘seeded’ with a piece of mantle tissue from a sacrificial oyster and a bead of polished mussel shell. This ‘seeding’ process involves surgical precision, with material carefully inserted into the gonad tissue of the target oyster. Once seeded, oysters are returned to the sea in net panels.
As a defence mechanism to the foreign material, the oyster encloses the nucleus in a membrane or pearl sac. Layers of nacre form around the nucleus, resulting in a pearl with a unique combination of size, shape and colour.
Over the next three months, panels are turned regularly to ensure that the pearls are round, and moved to sheltered waters where they are suspended on floating lines. It takes up to two years for the pearls to grow to desirable size and quality. The best oysters may be seeded several times, with each pearl larger than the one before.
The shell of the pearl oyster (known as mother-of-pearl) is also used in jewellery and for buttons.