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Facts and figures about Pearl.



Pearls - Very Cultured:

Pearls are an organic gem, created when an oyster covers a foreign object with beautiful layers of nacre. Long ago, pearls were important financial assets, comparable in price to real estate, as thousands of oysters had to be searched for only one pearl. They were rare because they were created only by chance.


Today pearls are cultured by man: shell beads are placed inside an oyster and the oyster is returned to the water. When the pearls are later harvested, the oyster has covered the bead with layers of nacre. Most cultured pearls are produced in Japan. In the warmer waters of the South Pacific, larger oysters produce South Sea cultured pearls and Tahitian black cultured pearls, which are larger in size. Freshwater pearls are cultured in freshwater mussels, mostly in China.


The quality of pearls is judged by the orient, which is the soft iridescence caused by the refraction of light by the layers of nacre, and lustre, the reflectivity and shine of the surface. Fine pearls do not have any flaws or spots in the nacre: it has an even smooth texture. Other factors which affect value are the regularity of the shape, size, and colour: rose tints are the most favoured.


Cultured pearls and natural pearls can be distinguished from imitation pearls by a very simple test. Take the pearl and rub it (gently!) against the edge of a tooth. Cultured and natural pearls will feel slightly rough, like fine sandpaper, because of the texture of natural nacre. Imitations will feel as smooth as glass because the surface is moulded or painted on a smooth bead.



Pearl Grading Pearl Lore Pearl Jewellery

Cultured pearls are the result of inserting a bead nucleus into a pearl oyster and letting it coat that nucleus with NACRE. Beads are cut from Mississippi River clams and sent to Japan where they are used to culture Akoya (salt water) pearls.


Pearls are graded on a number of factors similar to diamond grading. The 4 C's of pearls would be Lustre and Orient (colour), blemishes (clarity), shape (cut), and size (carat weight).


Lustre and Orient are the result of the thickness of the Nacre. Nacre is the coating that the oyster deposits over the bead nucleus inserted by the oyster farmer. The thicker it is, the more of a "sheen" the pearl will have. There is a brightness and surface play of colour somewhat like the sheen of an oil slick. The finer the pearl the sharper a reflection will be on its surface. A poor pearl will be dull and show little or no reflection. On a very fine pearl, you may be able to see yourself clearly. Pearls come in all colours.


It is normal to have some blemishes on the surface of the pearl. More blemishes mean less cost. Evenness of colour is also important.


Pearls come in a variety of shapes. Freshwater or Biwa pearls look like Rice Krispies although now the Chinese have developed round freshwater pearls. "Round" pearls are classified as round, semi-round, and baroque.


It is hard to find perfectly round pearls. Matching size and colour is also time consuming so a well matched strand can be costly.





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