The main argument to differentiate them is to know the different pearls species and to know it's natural colors , so that if appears a pearl with a different color from the natural one, we will know that either it is a surprise or it is radiated.

Base on practical effects a few type of pearls have sufficient number of nacre layers to be able to be radiated, reason why this treatment almost is reduced to Freshwater pearls and South Sea pearls (Australian's), so reduced size of pearls in colors like violet, dark grays and black, are usually radiated freshwater pearls, and pearls over 12 mm in silver colors usually are radiated South Sea pearls.

The irradiation practice in the South Sea is not as habitual as we think because of the Tahitinian's pearls, also in big sizes they are the unique ones that with no need of intervention of the man has dark colors.+BACK