This is an art deco era cloak clasp made of teal green coloured celluloid with a black design, over a metal base.  Each piece has three metal loops that you would use to affix it to cloth and one has a hook and the other has a loop so that you can fasten the two.  Each piece measures 2 5/8” in diameter and is in very good condition.  You could probably also use this as a belt buckle for an elasticized or decorative belt.  Nice quality piece - great to accessorize a cape, cloak or other garment!