Visible with the caseback, the oscillating mass with the motion is delicately engraved. It's made out of eighteen-karat gold and decorated by hand that has a barley grain pattern, accomplished by guilloche A gold Model encompasses a black dial and black leather-based strap, as well as an 18-karat gold pin-buckle https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/