Having already launched the Royal Oak in 1972 as the first luxury stainless steel sports watch with an integrated bracelet, Audemars Piguet sought to develop the Royal Oak into a diverse range of timepieces offering collectors a variety of complications. In 1985, the firm released the ref. 25594, featuring a sleek 36mm diameter case with calendar functions indicating the day, date, and moon phase.

The present example of the reference 25594 is cased in stainless steel and fitted with a striking electric blue dial, nicknamed “Yves Klein,” for its precise resemblance to the Nouveau-Realisme artist’s signature color. The Extract from the Archives confirms that this reference 25594 was indeed born with the “Yves Klein” blue dial. The petite tapisserie dial treated with this vibrant blue color gives a highly lacquered effect, glistening in contrast to the steel case and white printing. Very few steel reference 25594s have appeared fitted with such a distinct coloration, as standard versions were offered with cream, silver, or black dials. Moreover, “Yves Klein” dials were fitted to very few Royal Oaks across all references, subsequently becoming some of the most coveted variations. Its collectability is augmented by its wearable 36mm case, offered here in superb overall condition and complete with its original suite of accessories.