Pearl treatment is one of the steps to process pearls before they are put on the market.
There are many pearl treating methods. Irradiated pearls normally cost more than dyed pearls because the irradiation process is more costly and because it is usually reserved for higher quality pearls. Occasionally, some valuable South Sea pearl will be polished to perfect their luster. Therefore, treated pearl doesn't mean cheap or fake pearl. People just do that to get a more perfect art.
Read our Pearl Treatment part to learn differences between treated and untreated pearls.