Vintage Hand Knotted Glass Bead & Rhinestone 20” Necklace Clasp Replaced?

This vintage necklace features a unique tubular glass beads and rhinestones balls on hand knotted brown cord. The necklace measures 20 inches. The clasp has been replaced, I don’t believe it to be original. The material of the metal is currently unknown. This piece would make a great addition to any vintage or antique jewelry collection. The glass appears to have a brown film, and is more or less on each piece,this is old & I don’t know what the original design aesthetic was