Interesting, heavy, old necklace made with brass buttons

i really don't know much about strung beads at all, but this had a heavy, old feel to it so i bought it. while in line to pay, there was a man behind me buying a lot of beads and he was very interested in this piece. he told me it was a very good piece and valuable too. nothing else, so i still don't know much about it. there are brass buttons on each end and no clasp, so i don't know how it would have been held together.