Seen in the caseback, the oscillating mass from the movement is delicately engraved. It truly is created from eighteen-karat gold and decorated by hand that has a barley grain sample, finished by guilloche In case your Omega has the terms 'Grasp Chronometer' to the dial—as is observed during the Seamaster https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/