The first appears on the dial side: the Chronomètre FB 1.1-2 harmoniously combines an 18-carat white gold case with an 18-carat yellow gold dial. The distinctive design of the watch face offers a broad surface on which to express an exclusive finish: a hand-crafted patina. This patina is created using a combination of engraving techniques that require great manual dexterity. First of all, the gold is finely grained with a graver. The surface is then crafted at length using a tool called a "rocker", enabling the light to glide across the dial to the rhythm of the shimmering reflections of the moiré effect thus created. A symbol of the passing of time and of Ferdinand Berthoud's legacy, this combination of artistic techniques recalls the natural patina of the dial of the astronomical pocket watch No. 3 that inspired the Chronomètre FB 1.
 

Each of the five dials in this limited edition is hand-engraved and then subtly coloured to perfect the overall legibility. The FB 1.1-2 model, like Ferdinand Berthoud's original creations, is adorned with manual engravings that make it unique: "Ferdinand Berthoud - Chronomètre - Val-de-Travers - Suisse", followed by the individual limited-edition number, "N° X/5". Opposite these engravings are those indicating the power reserve of the movement: "Haut" and "Bas” (High and Low).

Another style of original finishes appears on the case-back side. For the first time, the FB 1 collection features a "pyramid" motif decoration adorning the entire surface of its three half-bridges, an authentic artisanal feat demonstrating the know-how of the Manufacture’s engravers. The material is cut free-hand with flawless precision and regularity using a graver. Already adorning two elements of the Regulator FB 1R, this "pyramid" decoration is inspired by the base of a clock by Ferdinand Berthoud, kept at the L.U.CEUM, in Fleurier. It is an astronomical measuring instrument, just like the astronomical pocket watch No.3 which inspired the FB 1.1-2 model. The latter thus reinforces its astronomical filiation by deploying the "pyramid" decoration on the back of the movement, offering an expressive new touch to the reverse side of the calibre which reveals the tourbillon, the barrel, as well as the fusee-and-chain transmission system.
 

This decoration also includes 18-carat gold cartouches bearing the inscriptions “Ferdinand Berthoud, Chronomètre Suisse 45 rubis". This is Chronométrie Ferdinand Berthoud’s first use of invisibly-screwed cartouches. They lend a new dimension to the back of the timepiece as well as aesthetic coherence, reflecting the finish of the tourbillon bridge.

The new FB 1.1-2 model in 18-carat white gold stands out in terms of the case itself, since some of its faces are adorned with baguette-cut diamonds for the very first time.

There are four in all: on either side of the crown and alongside the engraving of the limited-edition number facing it at 9 o'clock. In other words, the FB 1.1-2 model is the first creation in its lineage to feature gemsetting instead of the sapphire crystal portholes that historically revealed the key movement components.

This new five-piece limited edition radiates a sparkling, exclusive jewellery design. The crown is also set, a first for Chronométrie Ferdinand Berthoud. The exclusive choice of baguette-cut diamonds evokes the vertical pillar-type construction of the movement beating at its heart.
 

The second limited series, called FB 1.2-1, displays most of the characteristics of the 1.1-2 model. The movement, finishes and dial engravings are similar. The differences lie in the fact that its case is entirely made of 18-carat rose gold, as are the dial, lugs, fastening screws and three half-bridges visible through the back. For the first time, Chronométrie Ferdinand Berthoud has applied the use of rose gold to all these elements, thus ensuring a perfectly consistent appearance of the five FB 1.2-1 timepieces while giving a new glow to the FB 1 collection.

To accompany this unprecedented chromatic development, the Manufacture has chosen a set of hands in blued gold for the hours, minutes and power reserve and in blued bronze for the central sweep-seconds hand. The blue colour is reminiscent of the blue steel hands on the astronomical pocket watch No. 3 of 1806.
 

Finally, for a smoother transition between dial and movement, the chamfers surrounding the tourbillon have been polished by hand, as have those around the power-reserve indication. Within these openings (tourbillon and power reserve), the Manufacture alternates between straight-grained and circular satin-brushed decorations, thereby individually highlighting each component according to its position, material and function.