Bleaching and Pinking Pearl treatments

M

Magster

Guest
Does pinking and/or bleaching decrease the value/beauty of a pearl by damaging the nacre on the surface? I know that pearls all undergo a bleaching process so they appear whiter... bleach seems like a pretty harsh chemical to use on sensitive pearls.
 
The type of bleach used can determine whether or not damage occurs to the pearls.
Akoya pearls and freshwater pearls are almost universally bleached. Akoya pearls are very, very commonly pinked as well. The bleach can damage the pearls if it is too concentrated. The reason some factories use strong bleach is due to a quicker ROI. This can damage the nacre of the pearls, and this nacre can/will turn brittle, and may darken.
Pinking, on the other hand, does not seem to damage the pearls. It can actually increase the value of the pearls substantially, as creamy color pearls are much more difficult to market than rose color pearls. Pinking is typically easy to spot by looking for concentrations of color on the surface of the pearls, and in the drill hole between the nacre and the nucleus.

The easiest was to ensure you are not buying pearls that have been improperly bleached is to buy high quality pearls from a reputable dealer. These pearls will have a good thick nacre. Thin nacre pearls (cultured for only 6-9 months) are typical of the pearls you will find improperly bleached.
 
I would not base a purchase decision on whether or not the pearls have been bleached. This is standard practice, and if the seller claims the pearl strand has not been bleached I would suggest you request proof. This would be a very rare strand of pearls, if the pearls are Akoya or freshwater.
 
Are natural pink overtones more desired compared to treated pearls (pinking)? Treated pearls don't exhibit the same whiteness in body color. What type of treatment is used to create a silver overtone?
 
Natural is always better. You will find a lot of natural, light pinks in freshwater pearls, but rarely in Akoya. A problem with the Akoya is it can be very difficult to detect the pinking at times, with freshwater pearls it is a lot easier. If the pearls are deep pink, you can be nearly sure that they have been dyed.
The silver color can be obtained using silver dye. This color may, however, be natural in Akoya. A lot of harvested Akoya pearls are quite grey in color, straight out of the oyster that is. I would say at least 20% of any given harvest has this coloration. These pearls are typically dyed black if they cannot be bleached white, but the very nice ones are typically kept for sale. I have seen natural grey pearls (Akoya) that were not treated only to sell at local markets at low prices (for local Chinese). The quality was sub par, but the farmer was selling the strands for $1-$3 each. Barely covering his cost of the nucleus...
 
Pinking in freshwater and saltwater pearls is quite common because often it is preferred versus the plain white pearls. This procedure can be difficult to detect. Pinking can be identified through magnification of the drill hole or surface blemishes where the dye may be more concentrated.
 
You can also look at the drill hole for additional information. Most Akoyas will start cracking from or around the drill hole, exposing a bit of the nucleus...in the case of blackened Akoyas, the bead will also blacken (Akoya pearl bead are always pure white).

Hope this photo helps.

Douglas
 

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Black Akoya Pearl Pic

Black Akoya Pearl Pic

The picture of the Akoya shows a very dark coloration indeed. Was that pearl treated with typical dying treatments or harsher treatments such as a sliver nitrate dip. If the latter, it may explain the brittleness of the nacre and premature cracking.
 
Pinking and Bleaching

Pinking and Bleaching

Does pinking and/or bleaching decrease the value/beauty of a pearl by damaging the nacre on the surface?

No, not if done properly. Both bleaching and pinking enhance both the value and beauty of a pearl, thus the reason both are common industry practices for Akoya pearls.
 
Does soaking pearls in peroxide undo the effects of pinking?
 
It is peroxide first, then pinking as the final step.

Since this thread started 6 years ago, it has become possible to get very high quality untreated akoyas and untreated FW, probably due to the improved culturing techniques.

According to "the Book"*, pinking does not need to be disclosed, though other treatments should be.

*E. Strack, Pearls. See the books and resources section for more info.
 
right, but then say you soak them in peroxide again - will that take away the pinkish?
 
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