This is a vintage Japan faux white pearl with crystals and silver beads 2 strand necklace with hook closure.  It is adjustable and stamped "Japan" on the top of the hook. When hooked on the longest spot, the necklace is 9" long. You can tell the size of the faux pearls from the penny in the photo.  This was worn by my mother for many years until she was 101 and passed away in 2023.