Obvious with the caseback, the oscillating mass with the motion is delicately engraved. It can be comprised of 18-karat gold and decorated by hand using a barley grain pattern, done by guilloche A gold Variation includes a black dial and black leather strap, in addition to an eighteen-karat gold pin-buckle https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/