BIANCHET Tourbillon B1.618 Openwork Carbon Earth Limited Edition

To be unveiled at WATCHPRO Salon 2021 (12th and 13th November), the Carbon Earth edition of Bianchet’s Tourbillon B1.618 Openwork is limited to just 21 pieces.

Introduced in 2020 in a titanium version, the Tourbillon B1.618 Openwork watch by Bianchet is inspired by the work of Italian mathematician Leonardo Fibonacci and the Golden Ratio of 1.618. The new variant’s case is made of Carbon fibre & titanium powder composite and natural vulcanised rubber.

BIANCHET Tourbillon B1.618 Openwork Carbon Earth Limited Edition

Perfectly proportioned and true to the Golden Ratio, the carbon tonneau case of the new timepiece is braced with two soft vulcanised rubber ‘seams’ that underscore the case’s ‘golden’ arc. A Bianchet hallmark, they fulfil a design and engineering function while defining the chromatic theme, extending to the hands and hour markers as well as to crown’s rubber insert and the strap. Here, the earth tone chosen for the rubber underscores the connection to elemental materials and forces.

BIANCHET Tourbillon B1.618 Openwork Carbon Earth Limited Edition

The case measures 43 mm in width, 50 mm in height (length) and 13 mm in thickness. This watch can withstand shocks up 6000G and it is water resistant up to a pressure of 5 atmospheres (50 metres).

Its shorter lugs enhance both the case’s compact, purposeful aesthetic and wear comfort. The supple strap made from natural rubber is available in ‘Earth’ and Black.

BIANCHET Tourbillon B1.618 Openwork Carbon Earth Limited Edition

In this advanced, lightweight and incredibly strong composite, titanium powder has been added to the carbon fibres. The result is a moiré effect that alternates between shiny and matte in a random pattern unique to each piece. The combination with natural rubber, which also fulfils both a design and a functional role, only enhances the unexpected interplay of the primeval with the sophisticated.

The different textures, curvatures and seeming weightlessness of the Tourbillon B1.618 Openwork combine to provide a unique horological experience, making the watch a distinctive and natural extension of the wearer. Sapphire crystals on the case front and back offer an unobstructed view of the Bianchet B1.618 tourbillon movement.

BIANCHET Tourbillon B1.618 Openwork Carbon Earth Limited Edition

The plate, the gear-train bridges, and the tourbillon cage of this movement are made of titanium. A challenging material to begin with, it is doubly daunting when applied to horology, specifically the tourbillon. The titanium calibre is adjusted to 6 positions, ensuring an accuracy of -2 to +6 seconds per day. The lubricants are enriched with nano-diamonds, taking friction minimization to the next level.

Instead of following a traditional design that builds on concentric circles, which in effect only reflects the requirements of the mechanics, Bianchet has decided to make the Golden Ratio an integral part of its creation.

BIANCHET Tourbillon B1.618 Openwork Carbon Earth Limited Edition

As if a mathematical object in motion, the spiralling Fibonacci curves are found at the heart of the movement, evoking the double-mirroring of amise en abyme, less a stylistic effect, and more a measure of the young brand’s depth.

Several variations of hand finishing on the plate and bridges, each quite distinctive, emphasize the depth and intricacy of movement’s architecture and its dramatic arches. Every surface has its own finish, even those areas that are not readily visible, way deep inside. Polish, satin-finish, micro-blasting and circular graining play off each other in the light, while the deep black PVD coating contrasts with the reflections of the rhodium-plated wheels.

The movement provides a power reserve of 105 hours.

Technical details

Model: BIANCHET Tourbillon B1.618 Openwork– Carbon Earth

Materials: Carbon fibre & titanium powder composite and natural vulcanised rubber
Crown: Grade 5 titanium
Crystal: Sapphire crystal with antireflective coating, case front and case back
Dimensions: W 43mm x L 50mm x D 13mm
Shock resistance: 6000G
Water resistance: 50 meters (5 ATM)

Calibre B1.618
Materials: Main plate, bridges and tourbillon cage in Grade 5 titanium
Tourbillon: 60-second tourbillon, hand-wound, adapted to 6 positions; Antimagnetic tourbillon cage
Variable inertia balance wheel
Frequency: 3hz – 21,600 vph
Accuracy:-2+6 sec/day
Lubricants enriched with diamond nano particles to reduce friction
Finishes: Sand-blasted, circular-grained, satin-brushed titanium plates and bridges with a black PVD finish, hand-finished titanium tourbillon cage

Materials: Natural vulcanised rubber, Grade 5 titanium folding clasp
Available in ‘Earth’ and in Black


Swiss made: Imagined, crafted and hand-finished in Switzerland

5 years

Limited edition of 21 pieces

International retail price
55,000 CHF (WT)