From the birth of an oyster larvae to the harvesting of a cultured pearl takes time. For Pinctada Margaritifera and P. Maxima oysters this is usually over four years. Once an oyster is harvested it can be grafted a second and even a third time. If a third generation cultured pearl is harvested from an oyster this organism can be 8-10 years in age. Only oysters that have produced pearls with good shapes, lustres and qualities will be grafted a subsequent time. A new nucleus the size of the harvested pearl can then be inserted, which means that each subsequent generation of pearl cultivated in an oyster will be larger than the previous. Whereas, the size of the pearl increases with each generation, it becomes more challenging to achieve the qualities and lustres of pearls formed in younger oysters.
Pearls are typically harvested in colder periods. This is because these are periods when oysters secrete thinner layers of aragonite (the nacreous mineral), which in turn results in better lustres. However, harversting periods vary greatly between different pearl farms and depend on the size of operations, water temperatures, and the current health of oysters.