Noticeable in the caseback, the oscillating mass from the movement is delicately engraved. It's made out of 18-karat gold and decorated by hand that has a barley grain pattern, accomplished by guilloche Hailing from Redondo Seaside, California, Sean’s enthusiasm for design and style and all issues mechanical begun at beginning. https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/