This is a very nice vintage centerpiece necklace made of blue swirl glass. The oval centerpiece is suspended from a strand of graduated beads with filigree endcaps and it features five beaded drops. It fastens with a hook catch which allows the length to be adjusted. The metal appears to be silver plated brass. It dates to around the 1940s.
It measures about 16 inches and it is in very nice shape with some wear to the metal finish on the back.