How Can I Tell if a Pearl is Dyed?
Why do they dye pearls?
Off-colour pearls from the Akoya and silver-or gold-lip oysters are sometimes blackened to improve their appearance. Light-coloured pearls from the black-lip oysters are sometimes dyed because the lighter colours of this oyster tend to be less valued. Dyed pearls are not fakes, but they are normally considered less valuable than those of natural colour. How can you tell the if a pearl is dyed or has a natural colour:Pearls are dyed to improve their appearance. They are not fakes, but they are less valued than natural coloured pearls.
Dyed Pearls include:
Pearls from the akoya and silver-or-gold lip oysters that are off-colour.
Pearls from the black-lip oyster that are lighter colours.
Here are some of the things that will indicate that a pearl could be dyed: (compare pearls that are the same size, shape and overall quality).
1) Price - low price usually mean the pearl or pearls are dyed.
2) Size - if a pearl is less than 9mm and black, you can assume it is either a dyed akoya pearl or a black pearl with very thin nacre. Also, if the pearl is large and black remember that sometimes large round South Sea pearls are dyed black.
3) Colour - -it is unlikely to find several pearls that have the exact same even colour. This is especially true in a strand.
4) Shape -perfectly round pearls are rare. They are expensive. Suspect that they are dyed if the price is low.
5) Drill-hole Test- using a loupe, look to see if dye is concentrated around the drill hole.
6) Infrared Photo Test-photograph the pearls with colour infrared film. Naturally coloured pearls tend to look blue.
Virtually all Japanese cultured pearls are first bleached, then dyed and often polished by tumbling pearls in pumice or similar substances. Freshwater pearls are processed, bleached, dyed, and polished. Then treated with mild bleach, bright fluorescent lights and heat are used. The idea, as always, is to facilitate the matching of strands.
