Some would call this a faux moon stone but I believe it is a thermal plastic they used in the 1950's. It is a very soft blue and will compliment your tie. It is a slide bar that measures 2" in length with width of stone at ½". There is no maker's mark on this piece. I also have some cufflinks that match this tie bar that is on this site.
Jewelry Treasures From The Past
When you buy vintage you are buying classic memories!