Three strand pearl necklace help please

Hi guys,
Haven't had any finds for quite long, today found this three strand pearl necklace and as I know close to 0 about pearls, please help me ID them. They look to me natural as they are slightly different in shape and size, and have some tiny imperfections seen through the magnifying glasses, they are about 7-8 mm in diameter. Knotted strands also point to natural. If natural, are they freshwater or sea pearls, is it possible to distinguish? Haven't done the teeth test but somehow it does not feel natural to put pearls in my mouth . They look also quite recent, any idea about the origin - Chinese? No marks as far as I saw.

Thank you for looking, any thoughts are welcome!

 

C'mon now, IvaPan. Bite the bullet! (Ah...pearl)

 

I’m seeing peeling on those I’m afraid. What happens under UV?

 

Thanks, OBB, I didn't see peeling, this was the first thing I checked with my magnifier glasses. There are some blotches or uneven surface spots like on corals, not perfectly smooth, seemingly from the formation of the pearl. I managed to magnify and photo two such pearls with uneven surface. I also did the tooth test, felt gritty as if I taste sand.

 

Thanks, silverbell, for the encouragement, I did it, they definitely feel gritty on the teeth, like tasting sand. To be sure, I compared the feeling with the one from pearls from a necklace I am sure are artificial, and they felt very different, and very smooth. So I tasted pearls twice Not the best experience but useful to ID natural ones, I understand it. Everything in the name of science

 

Oh, that's better. I agree no peeling.

 

I didn't know pearls are also sensitive to UV, did the test with them and with the artificial ones for comparison, it looks to me that they glow. Will post the results in a while.

Thank you, OBB, for the tip on testing!

Any idea if these are freshwater or sea pearls? Is there a tip for distinguishing between the two?

 

UV test result.

 

dbm

 

I'd say freshwater pearls, just from experience. Those "wraps" on the ends of the strands made me think they were probably real before you confirmed it. Generally no one goes to the trouble for costume ones, although good quality ones might. I'd go over the clasp for marks just in case.

 

Thank you, evelyb30! I also suppose they are freshwater but just wonder if there is some decisive test that can tell. Probably no such test.
I will again look tomorrow for marks although I suspect they are modern Chinese production which is unmarked in most cases.
Thanks again!

 

Pardon me, what does it mean?

 

DBM = Deleted By Me. Sorry about that.

 

Oh, no problem at all! I thought it might be one of those colloquial things that native speakers use all the time, and which I don't get. Thank you for explaining!