Beautiful estate find! This does appear to be a costume piece. I believe the beads are some type of plastic??? Looks to be hand tied. Beautiful working clasp. Size reference photos included. The beads are a butterscotch/caramel color with a creamy color running through. They appear pearlized / marbleized. There are some imperfections like discoloration/aging on clasp, and black dots on beads. Please see photos carefully for any minor and/or manufacturer imperfections, signs of wear, aging, discolorations, etc.