IWC Portofino Monopusher Chronograph 18K White Gold ’Ardoise’ 8-Days Novelty Edition. The dial is ’Ardoise’ slate anthracite grey, with applied white gold Arabic numerals around a white luminous railway-style minute scale with white gold hour indices. It includes polished feuille leaf hands, and there are 3 recessed subsidiary dials with luminous white Arabic numerals and markers, and an 8-day power reserve indicator. It has a recessed running constant small seconds register at 6 o’clock, chronograph register at 12 o’clock, 8-day power reserve indicator at 9 o’clock, and a date aperture at 3 o’clock. Sapphire crystal exhibition case back. Powered by the manual-winding IWC calibre 59360 movement, constructed with 281 Components and 36 jewels. Fitted on a Santoni Grey Alligator leather strap with an 18k white gold tongue buckle. 

This IWC Portofino Monopusher Chronograph 18K White Gold ’Ardoise’ 8-Days 45mm Novelty Edition has a hand-wound IWC caliber 59360 movement. It’s rhodium-plated with fausses cotes embellishment, and it’s constructed with 281 Components and 36 jewels, a shock absorber mechanism, and a straight-line lever escapement. It has an indexless balance with four golden weight screws on the balance rim. The mechanism oscillates at a frequency of 28,800 vph (3 Hz).

At the heart of this remarkable watch beats a manual-winding IWC Monopoussoir chronograph movement, showcased through a sapphire skeleton exhibition case back. The Monopoussoir (mono-pusher) chronograph is one of the rarest and most demanding complications in fine watchmaking. Unlike conventional chronographs that separate the start, stop, and reset functions across multiple pushers, the Monopoussoir integrates all functions into a single pusher—a feat requiring immense mechanical ingenuity and flawless execution. Few watchmakers in the world possess the expertise to construct such a complication, and even fewer do so with the flair and sophistication of IWC.

Reference No. IW515103