Enamel through a system that requires eighty hrs. It comes in 18-karat white gold with many shades of green or in eighteen-karat pink gold with blue hues, equally accented with diamonds. The base steel of each is first sealed which has a transparent enamel and after that layers of opaque https://www.watchesworld.com/from-sean-to-daniel-tracing-the-evolution-of-james-bonds-iconic-watch-collection/