WilliamF said:
What are the value of freshwater pearls?
For small, irregular
cultured freshwater pearls? A few dollars for all those...
WilliamF said:
What is the easiest way to differentiate between freshwater and natural pearls?
None, really...
Between natural and cultured freshwater pearls... no shortcut for identification. None that I've ever heard of (which isn't allot saying). OK, the species used for cultivation are not the most likely for natural pearls, but that's not exactly a matter o identification - more of sleuthing.
There is nothing handy unless the look of the pearls happens to be typical for some type, and this is not the case with your pearls. The shapes and sizes and colors just hint that the pearls are not nucleated (most likely), whether they are freshwater or saltwater, cultured or natural... no clue.
The only way would be a lab report: the pearls would have high resolution X-Ray photos taken (no, the dentist's machine doesn't do that) and the identification will be based on the structure of the nacre layers throughout the pearl. I don' know all the criteria used... it isn't all that simple. But again, that's why there is need for those gemological laboratories in the first place.
WilliamF said:
Are freshwater pearls generally 100% nacre ?
Yes.
Bead nucleated freshwater pearls are still very unusual. And small ones... I don't really know nucleated freshwater pearls below 10mm are even supposed to exist anywhere.
The shape size and color of your pearls make me think they are '100% nacre' - tissue nucleated ones.
All this, as much as I know. I am ... just a pearl fan trying to help.
If the origin of these pearls makes you think they might be natural, you might as well want to have them tested. Well equipped appraiser labs might be more accommodating then the big institutions, but there aren't many specializing in pearls (run a search on this forum for "appraiser" and you'll find a couple), but you just need one... Certainly, the report of a widely recognized laboratory carries some clout, but that's yet one more choice for you