If you say they are natural, then I am guessing that they are American pearls... I've been through the
"n'ah they're 'druzy' cultured" a while back and a couple of such things with a lab report convinced me that there are 'druzi' natural pearl somewhere and you may be pleasantly surprised by the price tags on similar things.
The American Pearl Company has them and might be one place for you to find out a price - and market, if interested, for the pearls. Here's the link:
http://americanpearlcompany.com/pearl_guide/6.htm
(see the 'rosebud' pearls among the naturals)
Sure, there are cultured pearls that look like that and cost nothing (or whereabouts), so you may need a convincing ID for the strand, but that's another story. I cannot tell from pictures (and probably in person either!) just write this answer assuming you the pearls are natural. You will need proof.
Good luck!
