Aging Mikimotos?

[Mitulove]

Hello,
I have a vintage double-strand Mikimoto necklace from the 50s, I believe. I'm a pearl novice in the extreme, but looking at the pearls, I can easily point out a few that are distinctly more yellow than the others. Would Miki have strung such mis-matched pearls, or can they age over time? Some also seem quite bumpy to me. I can still see myself in the reflection, though not with detail. Any ideas? I have the box but not the papers, so no help to be had there. I can trace their ownership, so I know there was no switching out the Mikimoto clasp or anything.

Would restringing the necklace without the dodgily-coloured pearls affect its value much? I have a matching pair of twist-back earrings--would converting them to posts be advisable for similar reasons?

To have this set appraised, would you recommend going to the local Mikimoto authorized dealer? The pearls range in size from 3.5mm-7mm. Any ballpark figures over or under which I could be certain the person appraising them didn't know what they were talking about/having me on?

While I'm thinking of it, did Mikimoto ever sell rings or earrings from that time without the specific M in a clamshell stamp?

Photos follow, the second one being made with a flash.

Any help gratefully received.

 

[Valeria101]

Hello,

Would Miki have strung such mis-matched pearls, or can they age over time?

They age.... Frankly, I don't know much about why or how; clearly some pearls go through time better than others as there are really old ones hanging around just fine. I am not very familiar with old cultured pearls though to know what's happening.

 

[purepearls]

Some could have very well had a little more yellow than the others which may not have been as noticeable when they were new. That may be the reason they have been prone to yellowing faster than the others. Akoya pearls do tend to get more cream-colored over time.

Restringing without the darker yellow pearls may enhance the value a little. If you are interested in an appraisal, you should contact Sharon Wakefield. She is referenced many times on this forum and can be trusted for a solid valuation.

 

[Ashley]

Akoya pearls tend to yellow over time due to the thin nacre layers surrounding it's shell bead nuclei- the more exposure to various chemical agents and time, the faster the pearls will begin to display wear. Gradually the contaminants (i.e. tobacco smoke, perfume and sweat, etc.) begin to affect the crystallized layers and will stain them; Think about the habitual coffee drinker/smoker and their teeth... Less extreme effects in the case of pearls, but definitely there!

 

[Camelotshadow]

50 to 70 years old in the older days smoke filled party rooms, nightclubs lounges could definitely stain a pearl. They are porous so its not just a exterior stain but soaks into the pearl & most pearls are not polished off the outer layer with good results.
Many years of hot dry summers without AC can also add its affect. I don;t kow if pearls were originally more cream with rose but thats really all I see in the olderones & some down right beige.

Mikis skin is really no different than any other cultured pearl except they do have a timing now that takes them out when they are nacred the finest...I think in the cooler off cycle may lead to a nicer finish.

I have Mikis from the 60's that must have been well taken care of that Miki graded A+ & they are stunning but still cream with a more unusual silver overtone...They look as good or better than the modern mikis as Mikis are not cultured as long as they were in the older days & nacre is less thick.