This natural Silver White Pearl originates from China and its weight is about 4 carats. The measurements are 8.5mm x 0mm (diameter x depth). The shape/cut-style of this Pearl is Half-Drilled Sphere. This 4.24ct Pearl gem is available to order and can be shipped anywhere in the world.
Cultured freshwater pearls are produced by mollusks, but the process is started by human intervention. Cultured reshwater pearls are less expensive because they are faster to produce with higher yields per mollusk. More about treatments
Pearls are products of bivalve mollusks (mainly oysters and mussels). They are built up of nacre (mother-of-pearl), which is mainly calcium carbonate in the form of aragonite crystals, and an organic horn substance known as conchiolin that binds the microcrystals concentrically around an irritant. Although pearls are not especially hard, only about 2.5 to 4.5 on the Mohs scale, they are extraordinarily compact and very difficult to crush.
The typical pearly luster is produced by the overlapping platelets of aragonite and film of conchiolin nearest to the pearl surface. The color of pearl varies with the type of mollusk and the water, and is dependent on the color of the upper conchiolin layer. Pearls may be natural (occuring without human intervention) or cultured; and they may occur in the ocean or in freshwater.
These guys at Gem Select seem to be honest and straightforward to deal with, compared to many other sites in the gemstone business. They have a guaranteed return policy if the customer isn't happy with their purchase, but I haven't tested it yet.