Some haute horlogerie houses have talents capable of differentiating them from all the others and making them unique in some respects. One of the main features that distinguishes Audemars Piguet is, without a shadow of a doubt, his ability to skeletonize movements. All collections of the Le Brassus brand, from Millenary to Code 11.59 passing through the Royal Oak, have at least one skeletonized model and the last presented, at the beginning of October 2019, is the 26585CE, that is a perpetual calendar with black ceramic moon phases.

Let us try to understand better what we are talking about and ask ourselves some questions.

What is a skeleton?
Skeletonling means all those operations aimed at eliminating the superfluous metal from the caliber until it leaving only a slight frame that can act as a structure for the mechanical organs and that allows the vision of what is beyond it. This operation is of greater interest to bridges and plate and is still carried out mainly by hand, which is why it is an expensive activity reserved for watches of a certain importance, usually in limited edition.

How do I analyze a skeleton?
3 factors are taken into account to analyze a skeleton.

  • The degree of transparency reached in accordance with structural needs
  • Theinteraction of transparency with the design of the watch
  • The level of finishes and decorations used to finish the caliber

These, then, will have to be balanced according to the complications that the watch brings with it. A single time can have a much higher degree of transparency than a chronograph or perpetual calendar given the small number of components and the reduced inherent complication. The more "transparent", well-worked and technically innovative, the more valuable and relevant the skeletonizing is.

Why are movements skeletal?
There are many reasons why calibers are skeletonized. The first of these can only be aesthetic/artistic. The performance of such complex style exercises, in fact, is linked to the exhibition of the skill and talent of the master watchmakers who work for a certain maison. Stopping at this aspect, however, would be reductive, especially considering the direction that the watch market has taken over the last 15 years. There are numerous examples in which skeletons are used to show particular technical solutions,see The Scientist of Panerai, or are exploited to achieve a certain goal, such as weight reduction or impact resistance (see Richard Mille).

The Panerai Scientist

The skeletonization then becomes a means to experiment and innovate, where artistic mastery and balance are not the protagonists but fundamental means to increase the preciousness of the watch and raise it to a higher level.

Where does Audemars Piguet fit into all this?
The concept of skeletonization according to Audemars Piguet belongs to the second category previously exhibited and takes the name of Openworked. All skeletonized models of the brand present this adjective in their name. The philosophy of the maison is to create very balanced skeletonized calibers, symmetrical and without the use of excessively artistic finishes that would weigh down the final result. All the observer's attention must be focused on the technique and mechanical solutions used.

Mechanics is the protagonist of the watch and the talent of Audemars Piguet lies, in addition to using the solutions mentioned above, in manipulating it properly to obtain creations aesthetically balanced and pleasing to the eye, in accordance with the criteria described above. The ability to finish the caliber is already present, there are anglage and manual polishing of the highest level, but it is not the first detail that appears at the sight of the watch. Hiding the true preciousness of its watches behind more striking features, to leave them to true watch lovers, represents one of the signatures of Audemars Piguet.

In order to understand the different types of skeletons present to date in the collections of various brands, I will analyze with you three watches: theRM 055 by Richard MilleTheAudemars Piguet 15407 and the Cartier Santos De Cartier. All three are skeletonized time only.

Cartier Santos De Cartier

Equipped with the in-house skeletonized caliber 9611 MC with manual charge. Large Roman numerals at 12-3-6-9 along with the missing hour indexes help to create the support that the movement literally clings to. The plate has thus become the real skeletonized dial of the watch. The degree of transparency is decidedly high and the skeleton design is well integrated with the watch. There are no particular decorative finishes that would make it difficult to visually display time.

Richard Mille RM 055

The RM055 is fitted with the in-house caliber RMUL2 with manual charge. This watch is technically superseded and skeletonizing is a means of reducing the masses and inertness at stake; its purpose is, in fact, to resist the violent accelerations to which golfer Bubba Watson submits his watches while using the drive. Transparency is high, as is the variety of finishes used ranging from PVD coating, Tytalit treatment and manual polishing. The entire caliber anchored to the case through 4 supports equipped with shock absorbers capable of dampening the shocks perceived by the caliber itself.

Audemars Piguet 15407

The protagonist of this reference is the in-house skeletonized caliber 3132 with automatic charge. Despite the use of the burnishing of many components to highlight the technical innovation of the double barbell with its rose gold bridge, this caliber has a excellent degree of transparency (naturally reduced compared to the other two watches given the addition of the automatic charge) which is perfectly integrated with its design. The finishes are totally manual and very varied, we can in fact find polishing, anglage and perlage on almost all the components.

All three of these watches are united by the fact that the respective calibers were directly designed to be skeletonized, but have different solutions and purposes of the skeletons themselves. If with Santos we see how it is possible to achieve significant levels of beauty and harmony through intelligent design solutions, with the RM-55 we are catapulted into an extremely technical world where every detail is aimed at achieving a precise goal. In the midst of these two diametrically opposed worlds is Audemars Piguet's 15407 in which symmetry, color and shape balance and high manual finishes serve as a vehicle to highlight the high technical innovation represented by the double barbell.


As can be seen from this brief analysis, the world of watchmaking is large enough to accommodate different declinations and philosophies of thought within the same world of skeletons. Undoubtedly, however, Audemars Piguet turns out to be a step ahead of the competition: it manages to mix art and technique in a unique way.