The Portugieser Perpetual Calendar Tourbillon combines two horological complications on the dial.
ABOUT THE WATCH
Portugieser Perpetual Calendar Tourbillon
The Portugieser Perpetual Calendar Tourbillon unites two sophisticated Haute Horlogerie complications. The tourbillon, made of 82 individual parts, weighs only 0.635 grams. The "whirlwind" causes the balance wheel to rotate around its own axis, compensating for the effect of gravity on the oscillating system and increasing accuracy. Requiring no correction until 2100, the perpetual calendar automatically recognizes the different lengths of the months and leap years. The moon phase display is so precise that it will deviate by one day only after 577.5 years. The self-winding IWC-manufactured 51950 calibre boasts a power reserve of 7 days. The case is made of 18-carat Armor Gold®. Thanks to a modified microstructure, this material is significantly harder than traditional gold alloys. The blue dial, gold-plated hands and the 18-carat gold appliqués underscore the maritime character of this special edition, which is limited to 50 pieces and sold exclusively in IWC boutiques. The timepiece is fitted with a blue alligator leather strap.
Perpetual calendar | IWC Schaffhausen
In the early 1980s, IWC’s head-watchmaker Kurt Klaus set out on an engineering journey to translate the Gregorian calendar with its many irregularities into a mechanical program for a wristwatch. His ingenious perpetual calendar, which debuted in the Da Vinci Perpetual Calendar in 1985, comprises only about 80 parts and displays the date, day, month, year in four digits, and the moon phase. The smart mechanical program automatically recognises the different length of the months, and even adds a leap day at the end of February every four years. The moon phase display is so precise that it will deviate from the actual phase of the moon by just one day after 577.5 years. All displays are perfectly synchronised and can be adjusted simply by turning the crown. Some models come with an additional century slide, so the watch can continue showing the date until 2499. The calendar only needs a small adjustment in those centurial years that skip the leap year, which is the case in 2100, 2200, and 2300. Some versions of the calendar feature a double moon phase display, showing the moon phase on the northern and southern hemispheres.
Features
Case
Movement
Packaging
Rotor in 18-carat 5N gold
Pellaton automatic winding
Sapphire glass, arched-edge, antireflective coating on both sides
Power reserve display
Perpetual calendar with displays for the date, day, month, year in four digits and perpetual moon phase
Flying minute tourbillon
7 days power reserve
Limited to
50
pieces
Case
18 ct Armor Gold®
Case
Diameter
45.0
mm
Height
15.2
mm
Crown
Screwed-in
Back case
See-through sapphire glass back
Water resistance
3.0
bar
Calibre
51950
Calibre
Movement type
Automatic winding,
IWC-manufactured movement
