Engine-Turned Restoration is the careful conservation and repair of decorative engine-turned surfaces, also known as guilloché, found on metal objects such as clocks, silverware, jewellery, boxes and scientific instruments. Restoration focuses on preserving the original engraved pattern while cleaning, stabilising and sympathetically repairing areas of wear or damage. Maintaining the precision of the decorative engraving is essential to preserving the object\'s value and authenticity.