The Thinnest Sapphire Tourbillon Ever Crafted
- Aug 29
- 4 min read
When Transparency and Finesse Meet Lightness and Resilience :
The Story of the UltraFino Sapphire.
Sapphire has long been the material of dreams. Harder than steel, dazzlingly transparent, and resistant to scratches, it embodies purity like no other. But for watchmakers, it is also one of the most unforgiving materials: brittle to shape, nearly impossible to curve, and, when used for a full case, usually destined to result in heavy, oversized watches admired more in showcases than on the wrist.
With the UltraFino Sapphire, Bianchet challenges this narrative and rewrites it. Measuring just 9.8 mm, this is the thinnest sapphire case tourbillon ever created and one of the thinnest sapphire watches in the world, proving that transparency can be sculpted into finesse, and that a sapphire watch can be not only admired but lived with, day after day.
Carving Light into a Curved Sapphire Case
Creating a curved tonneau case in sapphire under 10 mm thick is an achievement few imagined possible. The crystal must be shaped with micron-level precision; the 1.2 mm curvature of the UltraFino makes each stage of machining exponentially harder. By using the latest sapphire cutting techniques, offering unmatched precision, minimal material loss, and the ability to cut complex shapes, Bianchet created an astonishing sapphire case that lets light flow freely, revealing the architectural skeleton of the movement in its purest expression.
This transparency is not fragile. The case is sealed with a visible white rubber joint that ensures 5 ATM water resistance, a feat rarely seen in sapphire watches. What is technical becomes aesthetic: the joint outlines the case in a bold graphic gesture, reminding us that at Bianchet, form and function work in harmony.
A Statement of Design Purity
Guided by the Golden Ratio and the natural harmony of Fibonacci geometry, the UltraFino Sapphire embodies Bianchet’s conviction that mathematics and beauty are inseparable. Every curve of the tonneau case, every openworked bridge, every proportion of the skeletonized architecture is drawn from this timeless code of beauty. In sapphire, this philosophy finds its purest expression. Transparency itself becomes a design language, where light outlines the geometry and reveals the rhythm hidden within.
The white gasket is not hidden, On the contrary, it is celebrated. Creating a clean graphic line around the case, it underlines the 1.618 proportion of the case, while turning a technical element into a design signature.
The result is not only a tourbillon watch, but a crystalline architecture of time. A piece where proportion, clarity, and movement converge into harmony.
Engineered Finesse with the UT01 Calibre
To create such a slim sapphire case required a movement of equal restraint and extreme finesse. Enter the UT01: an automatic flying tourbillon just 3.85 mm thick, yet shock-resistant to 5000 Gs.
Its bridges, sculpted from grade 5 titanium, are hand-finished, a labor of satin-brushing, sand blasting and polishing, including over 15 hours of traditional hand-chamfering. Around them turns a massive gold rotor, sculpted into twelve Fibonacci spirals, a kinetic signature of the Maison’s devotion to the Golden Ratio. At 6 o’clock, the flying tourbillon performs its aerial dance, uniting precision with poetry.
A Trilogy of Materials
Bianchet’s approach to contemporary watchmaking embraces materials more often associated with cutting-edge engineering than with traditional ateliers. The grade 5 titanium of the UltraFino Titanium offers exceptional lightness, strength, and corrosion resistance, while its integrated bracelet underscores a seamless architectural flow. The high-density carbon composite of the UltraFino Carbon crafted into both case and bracelet, delivers remarkable structural rigidity with an almost weightless feel, its deep matte finish revealing subtle layers of its construction.
Now, with the full sapphire case of the UltraFino Sapphire, Bianchet adds crystalline transparency to this material trilogy, uniting hardness, scratch resistance, and visual purity. In each version, high-tech materials are not employed for novelty alone, but as integral elements of design and performance, reaffirming that haute horlogerie can be as forward-looking as it is finely crafted.
A Sapphire Tourbillon Designed to Be Worn
The UltraFino Sapphire is not a fragile object for a safe. Its white rubber strap, secured by a titanium folding clasp, echoes the sealing joint of the case, creating a seamless flow of design. Soft yet durable, it ensures comfort, making the UltraFino Sapphire as wearable as it is admirable. A second black strap offers versatility, inviting contrast and seasonal change.
This exquisite timepiece stands as a clear statement that the impossible can be achieved, and that sapphire can be tamed into both transparency and finesse. It is the thinnest sapphire-case tourbillon ever crafted, and more than that, it is a companion of elegance and resilience, designed not just for admiration, but for life.
TECHNICAL SPECIFICATIONS
Case: Curved tonneau, full sapphire with white rubber joint
Dimensions: 40 mm × 47.5 mm × 9.8 mm
Water Resistance: 5 ATM (50 meters)
Movement: Automatic UT01 tourbillon in grade 5 titanium.
Tourbillon: Flying, in grade 5 titanium. Shock resistance 5000Gs
Finishing: Assembled and finished by hand, 15+ hours of hand-bevelling
Rotor: 18K massive gold, twelve Fibonacci spirals
Straps: White rubber with titanium folding buckle. Additional black rubber strap.
Guarantee: 5 years
PRICE
85 500 CHF (excl. taxes)
