This necklace is unmarked, but reminds me very much of Coro pieces from the period. It features a stylized bow with unusual keystone shaped red rhinestones and tiny clear chatons. The clasp is also decorated with small red stones. Altogether a classically forties piece!
Condition: Excellent, with age-appropriate surface tarnish. I believe the clasp and bow to be silver although, as noted, there are no markings.
Measurements: Neckline is 13.75 inches (34.9 cm), and the central feature is 2.5 by 2 inches (6.4 by 5.1 cm).