Have an attractive stamp you can spare and would like to show off? What better way than as a neckerchief slide?
Mount the stamp on a small piece of wood (any type) that's about 1/8" thick. Paneling scraps are good. Cut the wood a bit larger than the stamp so there will be an even border on all sides.
Sand all rough edges, then paint the wood. Use a color that complements the color of the stamp. Or try using a clear, non-yellowing finish for a natural wood background.
Enamel paint is best, but almost any paint will do. Test it on a scrap of wood first to see if you like it before painting your slide.
Attach the stamp with modeling cement or white glue. When it's dry, coat the entire slide with spray lacquer to protect it from dirt or damage. Don't use varnish or shellac, since both often yellow. Add a sheet-metal or wooden loop to the back with glue.