Vendome is the high-end, luxury subsidiary line of Coro, launched to compete with designers like Miriam Haskell
This is a 4-strand tiered statement necklace. with faceted Aurora Borealis (most likely high-quality Austrian crystal, which Vendome frequently used). You can tell by the sharpness of the facets, the clarity of the clear sections, and the way they cleanly reflect the light.
The crystal roundels are paired with textured, open-work gold-tone "cage" or filigree metal spacer bars/tubes. The clasp is a J-hook clasp (signed Vendome) with an AB crystal extender chain, allowing for adjustable length. Picture # 4 shows the length of approximately 22 inches and the piece is circa late 1950s to 1960s.