VICTORIAN/EDWARDIAN ? JET-BLACK-GLASS BEAD NECKLACE, MOURNING STYLE

Vintage , Victorian or Edwardian (?) style ' mourning' necklace Long black graduated-size bead necklace w faceted beads Approx 30" long tip to tip, so it has a 15" drop length These beads are on a thin black cotton (or silk?) cord, and the closure ends are tied together .One end ,only, has a tiny 'screw' tip (looks to be made of wood - which may help identify its vintage) See last 2 photos please. Due to its age I have not tried to un-knot it, in case the cord is delicate. It is long enough to just slip over your head , as it is , tied. Unsure what bead material is, seems like jet-black-glass ( doubt if plastic because of knotted threading at closure, but cannot guarantee) Thank you - Hope you like it