Pearls are formed when irritants (like sand, for instance) finds its way into the shell of a mollusc. In reaction, the mollusc begins to produce layers of nacre around the irritant. In natural pearls the irritant generally comes from the water its surrounded by, while in cultured pearls a piece of tissue is inserted by people to get the process started.
Traditionally, most natural pearls were found in the Persian Gulf. However, the majority of them have already been harvested, therefore natural pearls are tremendously rare. You may find small, natural pearls available for purchase, but they are costly.
This type of pearl is grown in a pearl farm. Molluscs are farm raised and once they are old enough, a technician will implant a mother-of-pearl bead. The molluscs are then returned to the water and cared for while the pearls are allowed to form.
Not every mollusc will produce a pearl, and not all of them will be of high quality. Over ten thousand pearls may need to be sorted through before a single princess length of uniformed pearls can be matched.
Pearls can be found in both freshwater and saltwater- additionally, various molluscs can produce different looking pearls.
These types of pearls are generally grown in rivers, ponds, and lakes- and predominantly in China. Many of these are white and generally resemble the Akoya Pearl in both size and shape. However, they can be produced in varying shapes, and a range of pastel colours.
The majority of freshwater pearls don’t have a bead nucleus, just a piece of tissue.
Imitation pearls are usually just a glass bead that has been coated. They tend to have a high lustre, but not in the same depth that is seen from high quality cultured pearls.
It should be relatively easy to separate an imitation pearl from a natural pearl or a cultured pearl. However, it can be challenging to differentiate between natural pearls and cultured pearls. Additionally, many pearls go through a treatment process to alter their colour, and enhance their lustre.