A combination of the twin crafts of enamelling and skeletonisation, the Jaeger-LeCoultre Master Grande Tradition Perpetual Calendar 8 Days Skeleton is the most elaborately decorated perpetual calendar yet to emerge from the manufacture.

Inspired by a Jaeger-LeCoultre skeleton pocket watch with a blue enamelled case from 1928, the Master Grande Tradition à Quantième Perpétuel 8 jours SQ features an open-worked movement, and grand feu enamel chapter rings – on the front and back of the watch. Unveiled at SIHH 2014, this demonstrates the degree to which Jaeger-LeCoultre is vertically integrated, with both the enamelling and skeletonisation are done in-house.  Made of solid white gold, the two rings are decorated in blue champlevé enamel, separated into individual panes by the hour indices. The enamelled chapter rings form a frame for the movement of the watch, just as in the Grand Reverso Ultra-Thin Skeleton.  But the enamel used for this perpetual calendar is a darker blue, so much so that the guilloche underneath the enamel is barely apparent. It’s worth noting that the Jaeger-LeCoultre enamelling workshop, led by Miklos Merczel, is accomplished and particularly known for its miniature enamel painting.

The calibre 876 is skeletonised in a modern geometric form, with lots of straight lines, especially on the three-quarter plate visible on the back. Much of the movement surface is decorated with hand-engraving, done in short, straight strokes which complement the aesthetic, but are simplistic in form and method. All the text on the movement is machined engraved.

The movement is manual-wind, which can be inconvenient for a perpetual calendar, but has an eight day power reserve so it only needs to be wound once a week. It is comprehensive, displaying all the calendar information on sub-dials with a frosted silver finish that go well with the cobalt enamel and blued steel hands. A feature that is common in JLC perpetual calendars but uncommon in general is the year display, on twin sapphire discs in the sub-dial at six o’clock. In addition, it has a night and day function as well as power reserve indicator at 12.

Using the case form now standard for most of the Master Grande Tradition complications, the white gold case has a diameter of 42 mm and is 11.6 mm thick. But the stepped, concave bezel make it seem slimmer. And the stepped lugs are another elegant detail.

The Master Grande Tradition Perpetual Calendar 8 Days Skeleton is a limited edition of 200 pieces with a retail price of 160,000 Singapore dollars, or about US$128,000.