Opera One sapphire dial

Originally developed to allow the time to be determined in the dark, the chiming of the hours and minutes remains one of the most difficult technical feats of watchmaking craftsmanship to achieve. To add to its complexity, the Opera One features a Westminster chime, which marks the hours using four hammers to play a melody of four different notes.

The mechanism is allied with another subtle technical feature: a Tourbillon. This complication, designed to eliminate the effects of gravity on the watch's regulating organ, represents a genuine tradition which Girard-Perregaux has maintained and developed since the 19th century, so much so that the superb architecture of its Tourbillon with gold Bridges has become a signature of the brand. The shape of the three characteristic Girard-Perregaux gold Bridges on this watch has been given a stylised redesign in order to incorporate the chime mechanism, revealing three of the four chime hammers with the fourth appearing when the chime sounds.

Another unique feature of this extraordinary timepiece is its tinted sapphire dial. This is adorned with a sunburst finish whose rays originate at the Tourbillon, producing a complex interplay of transparencies over the watch's exceptional mechanics. The dial reveals the Tourbillon at 6 o'clock while the hammers chiming the hour are visible at 9 o'clock. The case-back offers an alternative perspective on the highly complex movement.

The volume of the case gives the chime a crystal-clear resonance, which watch-lovers will appreciate not only as a remarkably complex technical accomplishment but also as an enhancement of the poetic charm exuded by this exceptional object.