NATURAL PEARLS
A natural pearl is exactly what it claims to be: created naturally without any human influence. These are pearls that form by chance as a result of an irritant becoming lodged in the mantle tissue of a pearl bearing mollusk, such as an oyster. Once lodged, the mollusk begins to wrap layers of nacre over the irritant, thus creating a pearl. Given that the original irritant influences the size, shape, and color, most natural pearls are oddly shaped and are less desirable than cultured pearls.
 
CULTURED PEARLS
A cultured pearl is formed when a pearl farmer insets an irritant, such as a mother-of-pearl bead, into the tissue of a pearl bearing mollusk. Once inserted, a cultured pearl grows the same way as a natural pearl. The main benefit of a cultured pearl is that by controlling the size, shape, and color of the irritant, a pearl farmer can influence the resulting pearls appearance, thus creating much more desirable and valuable pearls.
 
FRESHWATER PEARLS
A freshwater pearl is a pearl that is grown and harvested in freshwater rivers and lakes by pearl-bearing mollusks. Although freshwater pearls usually do not share the same lustrous shine or perfect roundness as their saltwater counterparts, freshwater pearls are extremely durable and less expensive making them a popular choice.
 
SALTWATER PEARLS
A saltwater pearl is a pearl that is grown and harvested in saltwater seas and oceans. These pearls are typically grown in oysters. Saltwater pearls are typically more desirable and more valuable than their freshwater counterpart. The most popular saltwater pearls include Akoya, Tahitian, and South Sea.
 
IMITATION PEARLS
An imitation pearl, sometimes called a faux pearl, are man-made pearls. These pearls are manufactured from plastic, glass, ceramics or other materials. Imitation pearls are typically sold as costume jewellery and do not have any gem value.
 
NACRE
Nacre, commonly referred to as mother-of-pearl, is the iridescent substance that lines the internal layer of a mollusk shell. Mineral secretions from the mollusk form this internal layer. This same substance is used by the mollusk in the creation of a pearl.