Beautiful WWII era folding "butterfly" type knife.  My opinion is that it was theater made or trench art crafted.  Components appear handmade.  The body is constructed from aluminum and brass.  Handles are inlayed with bone and shell and decorated with aluminum and celluloid dots.  Blade is stainless steel and is unmarked by a maker.  Has been lightly sharpened, still very bright and clean.  Very unique knife.