Visible through the caseback, the oscillating mass on the movement is delicately engraved. It really is created from 18-karat gold and decorated by hand which has a barley grain pattern, done by guilloche A gold version incorporates a black dial and black leather strap, and an eighteen-karat gold pin-buckle This https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/