AUDEMARS PIGUET | REF 25593BA REPETITION MINUTES, A YELLOW GOLD SKELETONIZED OPEN FACED MINUTE REPEATING WATCH WITH SAPPHIRE SET HOUR MARKERS, CIRCA 1986 | 愛彼 | 25593BA型號「REPETITION MINUTES」黃金鏤空三問懷錶備藍寶石時標，年份約1986

Audemars Piguet confirms that the present timepiece was sold in 1986 in the USA. 

To review a range of skeletonized Audemars Piguet watches contemporary to the present lot, see Brunner, G., Pfeiffer-Belli, C. & Wehrli, M., Audemars Piguet: 125 Ans d'Audace, pp. 90-93. It is interesting to note the variety of shapes and ornamentation of the illustrated examples, none of which are yellow gold and sapphire-set like the present example, and none of which are minute repeating models. 

According to literature, fewer than twenty examples of the minute repeating cal. 2850 were produced in in the late 1980s, of which the present lot is one. It can be surmised that those movements were fitted to a variety of cases, of which only a handful are known to be skeletonized, making this particular example one of an exceedingly small sub-group.

The design permits the beholder to experience the minute repetition both visually and auditorily.