The process for making patent leather -- specifically, the manner in which one side of real or synthetic leather is made very smooth and shiny -- was created by Seth Boyden in 1818. Initially, it was used mostly for horse harnesses.
It's flexible, waterproof, shiny, lustrous, and mirror-like. This finish can be achieved by coating leather with oil, varnish, lacquer, polyurethane, nitro-cellulose, or resin. Patent leather is most commonly used in shoes, but can be found gracing clothing, handbags, and all sorts of fashion accessories.