Over ten years ago, MB&F and independent Irish watchmaker Stephen McDonnell rethought the perpetual calendar from a blank sheet; now Geneva gem-setters have framed it in colour.
MB&F today introduces the LM Perpetual Chromatic Editions, three versions of the LM Perpetual limited to 8 pieces each. Two are in 18k white gold with blue sapphires or purple sapphires, and one is in 18k red gold with red rubies from Mozambique.
Each bezel carries 48 baguette-cut gemstones, set by hand in Geneva by the brand’s long-time partner STG Creation, without widening the case. The hands are PVD-treated to match: purple, blue, or 5N for the ruby edition. Beneath a suspended balance, the whole calendar sits in open view, with no dial in the way.
McDonnell’s mechanical processor starts from a 28-day month and adds days as needed, so no date is ever skipped. “I call perpetual calendars boomerang watches because they come back for repair so often,” says founder and creative director Maximilian Büsser.
The LM Perpetual won the Best Calendar Watch Prize at the GPHG in 2016; a decade on, it returns in a brighter coat of colour, the mechanism inside unchanged.
The Basics
Brand: MB&F
Model: LM Perpetual Chromatic Editions
Diameter: 44mm
Thickness: 17.5mm
Case material: 18k white gold (blue or purple sapphires) or 18k red gold (rubies); 48 baguette-cut gemstones, hand-set in Geneva
Dial: Dial-free display of the perpetual calendar beneath a suspended balance; skeletonised subdials; hands PVD-treated in purple, blue or 5N
Water resistance: 30m / 90' / 3 ATM
Strap: Hand-stitched alligator; folding buckle matching the case material
Limited edition: 8 pieces per edition, three editions
The Movement
Calibre: Fully integrated perpetual calendar, developed for MB&F by Stephen McDonnell
Functions: Hours, minutes, day, date, month, retrograde leap year and power reserve indicators
Winding: Manual, double mainspring barrels
Power reserve: 72 hours
Frequency: 18,000bph / 2.5Hz
Jewels: 41
Images courtesy of MB&F.