Watch ring in 18k (750 thousandths) yellow gold in the shape of a shuttle set with rose-cut diamonds. Transparent red guilloché enamel top engraved with gold lines showing an extraordinary technique. Enamel hour dial in excellent condition. Openwork ring running the length of the case, ending in arrow-shaped shoulders, revealing a perfectly engraved and thick tray support to accommodate the watch mechanism. The raised bevelled glass is in excellent condition. Mid-19th century. Manual mechanical movement with key (present). Enamel dial with blue and red coloured numerals. Minute divisions in gold dotted lines. Cylinder escapement. Access for setting and winding is via a remarkable slide bar under the case back. Very good condition. Functional at the time of the appraisal. Finger size : 54 Gross weight: 16.2 g. Expert's note: The art of guilloché came into being in the 18th century. It is a mechanical process of engraving on gold or silver by a guillocheur, a machine that engraves geometric patterns using cogwheels and cursors. This creates very precise, regular and repetitive patterns. In the case of this watch, the surface area is very small. To add complexity to the work, very fine gold wire decoration is applied and the whole is enamelled to perfection. This is haute joaillerie as much as haute horlogerie. Don't hesitate to ask the expert for his magnifying glass to delve into these remarkable details.