Awesome Silver Statement Necklace - Four Strands Marble/Glass Beads -Silver Clasp

I acquired this necklace along with many other pieces in a large lot from a jewelry store auction (the store was going out of business).  It was mostly black when I got it.  Some silver polish revealed this stunning silver pendant along with a silver clasp. The beads are glass but look like marble.  

It weighs 8 ounces.  No markings that I can find on the back but it does appear to be sterling silver.  Approximately 16" long.

Thanks for looking!