Visible with the caseback, the oscillating mass from the movement is delicately engraved. It is constructed from eighteen-karat gold and decorated by hand using a barley grain sample, done by guilloche In the event your Omega has the words 'Learn Chronometer' about the dial—as is seen while in the Seamaster https://www.watchesworld.com/understanding-the-complex-world-of-chronometers/