Dyed Freshwater Pearls

[perlas]

I have been avoiding dyed freshwater pearls although a lot are really pretty and even classy.

Since I have not actually kept a subtantial number of dyed fwp strands, I would like to get inputs on those who have.

Do they fade through time? Do they lose their luster? I've actually seen faded dyed fws and some with sort of white spots but I don't own them myself (were the pearls just poorly dyed or did they fade through time?). Do this changes happen in dyed top-grade pearls?

Would be interested in your experiences.

 

[Satine De La Courcel]

I have been avoiding dyed freshwater pearls although a lot are really pretty and even classy.

Since I have not actually kept a subtantial number of dyed fwp strands, I would like to get inputs on those who have.

Do they fade through time? None of mine have, But that is my experinece,


Do they lose their luster?

all pearls can loose luster, depending on their use, how they are handled and how hard they are worn. IMO


I've actually seen faded dyed fws and some with sort of white spots but I don't own them myself (were the pearls just poorly dyed or did they fade through time?).

I think they were poorly dyed usually though wiht a poor dye job you can see in and blemishes on the pearl where the Dye will "collect", I have seen some white spots on natural pearls where that is how they were formed in the mollusc one pearl like that is teh palitinte pearl it is half white and half black a natural not dyed and another is the hope pearl also natural where it is multi colored...

as far as this kind of theing I see it somewhat often with my "bead Grade pearsl I use"

which are a few rungs below what other beaders here get their hands on... But for Garb it can be...
Do this changes happen in dyed top-grade pearls? Um doubtful

All pearls can wear. it is how they ar handled and how they degrade makeup etc... I think someone has been giving dyed FWP a bad rap most FWP are dyed NOT all but most these days.

Just my feew experiences and opinions woul dlove to hear what others have to say as well..

Cheers

Ash

 

[jshepherd]

It really just depends on the factory processing the pearls. The dye treatment is never the same from company to company. Every company mixes their own dyes and chemicals, and these are closely guarded secret formulas. With some dye jobs you will see spots, speckling, light areas, color concentrations, etc. But with other dye jobs you may see a perfectly static color and no concentrations.

The color can fade, especially if left in the sun - it will bleach. But even natural color freshwater pearls can fade.

 

[cowgirlsalon]

Although I am a virtually non-posting member, I had a recent experience regarding dyed freshwater pearls that I couldn't resist sharing:

I recently discovered in my backyard the remnants of a rather unattractive unfinished strand of pearls that had been dyed bright green and which my cat must have not liked either, as he's the only one around here who would have taken the strand outside and attempted to bury them by the fence. Though they initially appeared to be white pearls, closer inspection revealed green dye around the drill holes and the sides of the pearls which hadn't been exposed to sunlight all winter tended towards a beige-ish color rather than white. I can't say that spending the winter outside did much for their luster, but that could partly be due to having been exposed to the elements for many months. If I can remember where I put the pearls (or find any that I missed outside) I'll take some photos before and after I attempt to clean them up a bit.

ITM, I attached (or at least attempted to attach) photos of two dyed cfwp strands and a dyed pendant that I have worn a considerable amount with no discernable fading of color.


Sincerely,
Annie M. Harrison

 

[Satine De La Courcel]

y to company. Every company mixes their own dyes and chemicals, and these are closely guarded secret formulas.

No Surpise there!


The color can fade, especially if left in the sun - it will bleach. But even natural color freshwater pearls can fade.

I knew Conch can fade if left in sunlight too long. but did not equate it with other types of pearls... I should really pull my head out of the history books and study some stuff about modern pearls.. LOL

Thanks Jeremy!


Ohh Dyeing ones own perls.. some day I will experiment with "historical methods" of Dyeing and play with that and pearls.. Sigh there is never enough time to do all the fun stuff I want to do and conquer the world...

Cheers
Ash

 

[perlas]

Thanks for the feedbacks!

That means as the dyeing technology improves... more affordable, beautiful pearls will be available...

On the other hand, this will post as a problem for natural colored pearl collectors. Maybe soon everybody needs a lab to distinguish if their fwps are dyed or not!

 

[Valeria101]

...I should really pull my head out of the history books and study some stuff about modern pearls.. LOL

Maybe not... I think Streeter was the first place where I heard of pearl bleaching (by exposure to sun light)... and a similarly aged source about (natural) dies, etc. Good to know how old the concept really is.

Since at least some of those old 'treatments' are precisely those accepted w/o impact on value today, old books are really useful, IMO.

 

[Satine De La Courcel]

Maybe not... I think Streeter was the first place where I heard of pearl bleaching (by exposure to sun light)... and a similarly aged source about (natural) dies, etc. Good to know how old the concept really is.

Since at least some of those old 'treatments' are precisely those accepted w/o impact on value today, old books are really useful, IMO.

Okay while digging about on an umralted pearl thing I can not confirm it but there may have been "sun bleaching" practices for pearls in the 1500's I do not ever remember this e-mail at all.. IF I can find out more I will post....

BTW I am waiting for the reprint of the streeter book... will see if that everh comes to light...

Happy Friday Everyone!

Cheers
Ash

 

[perlas]

Most of us have discussed about spotting fake pearls from real ones but I've noticed that we seldom discuss dye detection in pearls.

I tried to rub 70% alcohol in dyed FWPs and the dye doesn't come off. That means dyeing technology is greatly improving.

All commercial pearls now are being dyed to imitate their natural color (Goes for south seas, tahitians, akoyas, and fwps).

I've checked the Liddicoat Book of Gem Identification and thought some might be interested.

1:20 part of nitric acid may rub off some dye in pearls.
a drop of hydrochloric acid may leave a dark spot in the pearl but be sure to wipe it off immediately as it may totally ruin the pearl.

However, when doing above, be ready to have a sacrificial pearl.

It might be expensive to ruin a nicely dyed south sea but might be worth doing to test if a nice freshwater strand is dyed...

 

[DFrey]

Hi Perlas,
You could try the 99% solution of alcohol, isopropyl that is, it may work better than the 70%. Pure alcohol is used in a lot of labs as a all round solvent. I used to use it on a cotton swab to test lapis beads etc to see if they were dyed. But you may be right that the new dyes are not detectable using solvents like alcohol.
Dfrey

 

[perlas]

Hi Dfrey, The dyes used in the stones are different and a lot would rub off from alcohol. However, for pearls, they probably keep on doing research on dye improvement to keep the luster of the pearls and the orient even when dyed...but I haven't tried 99% alcohol though...

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Don't know if it's ok to quote below... mods, please delete if it violates anything.

From: Handbook of Gem Identification, Richard T. Liddicoat, Jr.

Detection of Artificial Color in Black Pearls. Page 128

...black dye can be detected by rubbing it with a white swab soaked in a weak solution (1:20) of nitric acid; the swab will be slightly discolored. Other pearls however, are treated in a manner that attackes conchiolin and turns it black, and acid swabs will not detect it. Still others are soaked in silver salt solution, such as silver nitrate, and exposed to light precipitate free silver. These show white streaks on the x-ray (silver is opaque to x-rays).

Naturally colored black pearls usually fluoresce pink to red under long-wave ultraviolet light; treated blacks either fail to fluoresce, or have a whitish fluorescence. A few natural blacks fail to fluoresce, but these are distinguished by the presence of green, rod-like inclusions in a near transparent surface layer. Otherwise, a failure to fluorescer in a reddish color is satisfactory evidence of artificial color.

Acid and Solvents. Page 164-165

Acids, particularly dilute hydrochloric acid, is very useful in testing, serving a variety of purposes. For example, any of the carbonates such as calcite (which, when dyed, is used to imitate jade - the so-called Mexican jade), coral, shell, pearl, smithsonite, malachite, and rhodochrosite are revealed by pronounced effervescence when a drop of dilute hydrocholic acid is placed on the surface. On malachite and azurite, which are copper carbonates, the spot turns yellow-green.

Caution: Since hydrochloric acid attackes the surface of any carbonate quickly and strongly, it should be wiped off after the slightest touch and the spot quickly washed with water.

...Cultured and natural pearls are dyed black by various methods, some of which leave a surface stain detectable with acid-dipped swab. For this test, a swab dipped in a dilute solution (1:20) of nitric acid and rubbed against a pearls shows a faint dark stain, revealing the dyed surface.