A small early 19th Century Swiss watch with visible diamond set balance in a gold and enamel diamond set shield shaped case. The unusual full plate cylinder movement following the form of the case with the balance visible on the front. Very slender bar supporting the diamond endstone, four arm balance bearing four small diamonds. The balance above a blue steel ground decorated with a polished steel cross. Below the balance a small white enamel dial of Arabic numerals, blue steel hands. Blue and white champleve enamel mask bearing two serpents frame the balance and dial. Rock crystal cabochon protecting the dial and balance. The front and back borders of the case set with graduated diamonds of varying cuts, diamond set gold bow. Hinged gold back, polychrome enamel floral decoration on translucent dark blue enamel over an engine turned ground. Under the lid the winding, setting and adjusting squares. Slender gold key set with three diamonds, the top reflecting the shape of the case. Small red morocco presentation box.