This is a plastic choker from the 1956 Coro collection called "Moonray".  15 square plastic cabachons glow like moonstone in this pretty necklace that is a shade in between white and a bluish grey.  It is joined together in links of shiny silvertone making it very sturdy and flexible.  It has a hook closure and additional links ending in a silver ball.  The stones measure 11 1/4" with an additional 6 1/4" of chain.