Pearls are produced by mollusks including oysters, mussels and clams. However, mussels and clams rarely produce them while oysters commonly produce them no matter if they are in freshwater or in saltwater.
The idea that pearls are produced from sand intruding into the shell of an oyster is false. Sand is an inorganic material while the gems are formed by organic materials that are caught inside the oyster. As a defense mechanism, the oyster wraps the organic material with a substance called nacre, resulting to what is known as mother of pearl.
Most people believe that pearls should have an imperfect form since they are products of nature. However, there are those that are formed perfectly and these are considered very valuable pearls. Unlike the common belief that pearls are usually white, pearls come in various colors like black, green, red and even blue. Different-colored pearls can be found all over the world but only the South Pacific has produced black pearls.
Among the kinds of pearls are cultured pearls either in saltwater or freshwater. South Sea pearls produced by golden lipped oysters and are cultured in Indonesia and Tahitian pearls or black pearls that are produced by black lipped oysters and are cultured in Cook Islands or in the French Polynesia.
So how can one determine if it is real or an imitation? Real pearls tend to feel sandy when rubbed along the edge of the front teeth while imitation ones fell smooth.
Aside from the kinds of oyster from which pearls are produced, the quality is determined according to their luster or shine. Thick nacres that have been left in the water longer are generally shinier. The shape is also important and the rounder, the better. The larger the pearl, the rarer they are and the more expensive.
There is a legend that Cleopatra dissolved a pearl in a glass of wine before drinking it, simply to win a bet with Marc Antony that she could consume the entire wealth of a nation in just one meal. However, in another version of that story, it was intended to help her win Antony’s heart. In ancient Rome, the pearl was the decisive symbol of affluence and social standing, while the ancient Greeks associated it with love, marriage, and unrivaled attractiveness. The Greeks also believed the pearl would encourage marital accord and prevent new brides from crying. During the Dark Ages, knights wore pearls on the battleground, believing they had the magic to shield them from injury.