Shape

If the white japanese pearls are all round, the black pearls offer to the enthusiasts a wide choice of shapes. Beginning with the perfect sphere, they run the gamut from button to pear to encircled to oval to the complete baroque construction. Some shapes are particularly original and are much in demand, but the classic round pearls and those in the shape of a pear remain the surest investments.

  Round Pear Baroque Encircled
Cat. A Round category A Pear category A Baroque category A Encircled category A
Cat. B Round category B Pear category B Baroque category B Encircled category B
Cat.
C		 Round category C Pear category C Baroque category C Encircled category C
Purity

 If you take a black pearl in your fingers an examination permits one to detect the defects that can mark a black pearl. If the pearl is not mounted, just one small, very localized defect can make it possible to buy it at a lower price than if it were perfect. Afterwards, it can be mounted in such a way that the miror defects is totally concealed by the mounting. It is extremely rare to find a pearl that the miror defect is totally concealed by the mounting. It is extremely rare to find a pearl that is totally exempt of all microscopic imperfections, a pearl that is totally exempt of all microscopic imperfections, a pearl deserving to be regarded as "naturally perfect".

Category Orient Lustre Faults
A+ very deep very high none
A very deep very high infinitesimal (-10% of the surface)
B very deep high some (less of 1/3 of the surface)
C deep medium some (little more than 1/3 of the surface)