lot 15


Perpetual Calendar

Estimate CHF 10 000 / CHF 15 000
Starting bid CHF 10 000

Hammer price CHF 19 000
Total bids 10
All prices do not include 24% Premium


CaseRose gold case 750/1000 with sapphire caseback
StrapBrown Alligator, with original IWC rose gold folding clasp
DialWhite dial, with applied rose gold arabic numerals, moonphase indication at 12 o'clock, date and power reserve at 3 o'clock, month indicator 6 o'clock, year indicator 7 o'clock, weekday and small seconds at 9 o'clock
MovementRhodium-plated movement, with double barrel 7 day power reserve, breguet hairspring, and perpetual calendar
Movement No.4328873
Case No.6084238
D=44.5 mm

Condition report

Case:Very good, only small signs of use
Strap:Very good, looks like new
Dial:Mint condition
Movement:Very good, all functions are working properly
Amplitude (Dial on top/Lift angle 52):ca. 300 degrees
Accuracy (Dial on top):+ 9 s/day


A very fine, large and attractive 18k rose gold wrist watch of the famous Swiss watch brand IWC Schaffhausen, founded in 1868. Purchase year: 2019. 18k rose gold case, diameter 44.2mm, 14.9mm thick, white silvered “sunken” dial with rose gold-toned applied Arabic numerals, indexes and hands, all four sub-dials with fine circular grooves, sapphire caseback. Caliber 52610, stamped with the Probus Scafusia quality seal, with Pellaton self-winding, skeletonized solid gold rotor with Probus Scafusia medallion, power reserve up to 168 hours. Functions – indication of time in hours and minutes, small seconds at 9 o’clock, power reserve indicator at 3 o’clock, perpetual calendar with indicators of the date at 3 o’clock, day of the week at 9 o’clock, month at 6 o’clock and 4-digit year between 7 and 8 o’clock, moonphase at 12 o’clock. Brown leather strap, 18k rose gold IWC Schaffhausen double folding clasp. 

Lot essay 

The history of IWC Schaffhausen wristwatches with a perpetual calendar is intriguing. The brand was one of the first to enter the market with the offer of an automatic perpetual calendar for serial production – the first watches were produced in 1985. A special feature of the then development, undertaken by Kurt Klaus, technical director of IWC Schaffhausen, was the use of a third-party automatic chronograph movement, the Eta/Valjoux 7750, as the base caliber, and an in-house perpetual calendar module, simplified, which was set to automatically follow the current calendar, and the evolution of the moon phase without the possibility of separate correction of the indicators. Therefore, the calendar module was equipped with an accurate moonphase indicator, designed to accumulate a deviation of one day in 122.6 years, compared to the usual time of approximately two and a half years. The mechanism turned out to be robust and reliable, and there were no problems with ensuring water resistance since all four correctors, needed for the perpetual calendars of the standard design, were not required here. This allowed the use of the Da Vinci Ref. IW3570, which pioneered the developed calendar, as a daily-wearer, and the watch turned out to be very popular. 

In 2000, for its in-house calibers, IWC revived a famous invention of the 1950s – the Pellaton automatic winding system. After the successful launch in 2000 of the new Portuguese Automatic with caliber 5000, one of the best automatic movements in the industry with a 7-day power reserve, the brand decided to adapt the perpetual calendar of Kurt Klaus to this movement. It was necessary to switch from the 30mm Eta/Valjoux 7750 to the 38mm 5000 caliber, which required a complete redesign of the calendar module. Though it is basically the same module as used in the Da Vinci, the accuracy of the moonphase complication was optimized from one day out in 122 years for the Da Vinci to one day out in 577 years for the newly developed Portuguese Perpetual Calendar. The first Portuguese Perpetual Calendar, reference Ref. IW5021, was launched in 2003. In 2006, the original Ref. IW5021 was accompanied by the slightly smaller 42.3mm Ref. IW5022, which was replaced by the 44.2mm Ref. IW5023 in 2010. 

The Ref. IW503302 is equipped with a 7-day caliber of the latest generation in the ‘Single Moon’ version, and this is an excellent opportunity to complement the collection with an up-to-date perpetual calendar with good collectible prospects.

In 2015, IWC celebrated the 75th Anniversary of the Portuguese watch with the introduction of a relaunched collection and the name, changed to Portugieser, with new Portugieser Perpetual Calendar references IW5033 and IW5034, which replaced IW5023 and IW5021, respectively. Besides a number of changes to the design, including a slimmer case and domed sapphire crystal, the watches of the new generation were powered by twin-barrel calibers of the 52000 family, while the calibers of the previous generation 51000 family had at their disposal a single barrel. The Portuguese Perpetual Calendar Ref. IW5033 was fitted with the caliber 52610, featuring a higher balance frequency of 28,800 vph. The movement was redesigned with new bridges, a solid gold rotor and blued screws, a rotor bearing in white ceramic, winding pawls and Pellaton rachet wheel in black hi-tech ceramic, and a Breguet hairspring. Ref. IW5033 was offered in a variety of options, including Ref. IW503302 in 18k rose gold and silvered dial, as the present example, and a number of references in 18k white gold, 18k rose gold, platinum, and stainless steel, including limited editions. 

The present lot represents the current stage in the evolution of the Portugieser (formerly Portuguese) line of perpetual calendars. The Ref. IW503302 is equipped with a 7-day caliber of the latest generation in the ‘Single Moon’ version, and this is an excellent opportunity to complement the collection with an up-to-date perpetual calendar with good collectible prospects.

Reasons to bid 

The Portugieser Perpetual Calendar ‘Single Moon’ Ref. IW503302 would appear to be a fine purchase for the collector looking for a complicated mechanical watch from a world-famous watch brand, one of the market leaders in calendar wristwatches. IWC Schaffhausen calendar watches are an excellent collectible, while the present lot represents the current page in the development of the brand’s perpetual calendars, where Kurt Klaus’ innovative and popular perpetual calendar design is complemented by a modern self-winding Pellaton caliber, another striking historical technical achievement by IWC. At the same time the large 44.2mm 18k rose gold case of Ref. IW503302, its self-winding 7-day power reserve Pellaton caliber and Kurt Klaus’ practical and easy to use perpetual calendar complication perfectly match modern tastes, making the present watch an almost perfect daily wearer. 

N. B. 

The keen collector should note that also offered for purchase in this sale is another fine and attractive 18k rose gold ‘Single Moon’ perpetual calendar watch – Portuguese Perpetual Calendar Ref. IW502213. Together with the present lot, they represent the impressive timeline of this complication in IWC Schaffhausen collection over the years.