Patek Philippe. A very fine and rare 18K gold openface minute repeating perpetual calendar split seconds chronograph keyless lever watch with phases of the moon and champagne dial

Patek Philippe. A very fine and rare 18K gold openface minute repeating perpetual calendar split seconds chronograph keyless lever watch with phases of the moon and champagne dial
Signed Patek Philippe & Co., Geneve, movement no. 197'663, case no. 412'649, manufactured in 1921
Cal. 19''' nickel-finished lever movement, 39 jewels, bimetallic compensation balance, swan neck regulator, wolf's tooth winding, repeating on two polished steel hammers onto two gongs, gold cuvette, the champagne dial with Arabic numerals, outer Arabic five minute divisions, blued steel spade hands, four subsidiary dials indicating phases of the moon combined with 60 minutes register and lunar calendar, day, month and date combined with constant seconds, in heavy circular plain case with hidden hinges, repeating slide in the band, split seconds chronograph mechanism operated through the crown and through a button in the band, locked by a sliding lever in the band, case, cuvette, dial and movement signed and numbered
54 mm. diam.