Noticeable through the caseback, the oscillating mass with the motion is delicately engraved. It is comprised of eighteen-karat gold and decorated by hand using a barley grain pattern, accomplished by guilloche When your Omega has the words 'Grasp Chronometer' about the dial—as is seen while in the Seamaster Diver 300M—it https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/