Nowadays, pearls are cultivated around the world. They develop under controlled conditions in both saltwater and freshwater by inserting a microscopic irritant into the mollusc. Farmers keep the oysters in sheltered bays with nutrient-rich waters where the molluscs feed and grow, coating the irritants with layers of nacre and creating pearls.
It takes between six months and four years for a pearl to form, and the farmers have to take utmost care of oysters during the whole period. They feed the oysters, check for organisms that may interfere with their feeding, treat their shells with medicines to prevent parasites and ensure that water conditions are optimal for the development of gems.
When the pearls are ready to be harvested, the oysters are sent to harvesting facilities. Harvesters carefully open the molluscs and remove the pearls using special instruments. This is an extremely delicate process and requires gentle hands not to damage the gems during the harvesting.
It is worth mentioning that most oysters are killed in the harvesting process. However, the oysters that produce the best-quality pearls may be re-nucleated. Farmers insert a new nucleus and grow another pearl inside of the same mollusc, as pearls grown by older oysters have a higher quality and are usually larger than first-generation gems.
Once the harvesting is complete, the pearls are subjected to cleaning. This includes soaking them in a cleaning solution to remove dirt and odours. If required, pearls are getting bleached and polished. Then gems are matched by pouring them into large sieves that separate pearls based on their size. Further, pearls are graded and categorized according to their quality factors.