Vintage Textured Silvertone Atomic Cufflinks

These are shiny & look brand new but they are from the 50's or early 60's. On each side of the cuff links on the face & the back have different textures. I'm not sure if the black is onyx or enamel but it feels like it's a stone vs enamel. It has a center faceted stone which looks like a diamond. Not sure if it is plastic or not. They're very elegant looking and in amazing condition! No markings that I can find of the maker . Slightly smaller than a nickel, if a nickel were oval😁