Greubel Forsey

Greubel Forsey

August 1, 2018

A New Light

Greubel Forsey casts the Double Balancier in a fresh light with a new limited-edition version presented in a sapphire-crystal case.

After Robert Greubel and Stephen Forsey started their signature brand in 2004, one of the first things they did was create the Experimental Watch Technology (EWT) program. Since it was established in 2005, this in-house R&D department has been a powerful conduit for the founder’s curiosity as they pursue new ways to improve performance in mechanical watchmaking.

Over the years, work done by the EWT has fueled the expansion of Greubel Forsey’s horological universe through a series of patented designs the company calls Fundamental Inventions. The sixth of those inventions — the Double Balancier — was patented in 2007. When the first models arrived in 2013, the watch world had never seen anything quite like it.

The first Double Balancier was released in 2013 after six years of research and development.


The same is true five years later as Greubel Forsey revisits this unconventional design with the new Double Balancier Sapphire. Limited to 11 pieces, this special timepiece is only available through authorized retailers in North America.

For centuries, watchmakers have searched tirelessly for ways to reduce gravity’s negative impact on chronometric performance. One of Greubel Forsey’s most interesting contributions to this age-old tradition is the Double Balancier, a timepiece designed to minimize the effects of gravity and maximize timing precision while resting a in stable position.

How does it work? In a mechanical wristwatch, the oscillator — which includes the balance wheel, hairspring and escapement — is largely responsible for maintaining the timekeeping rate. As a general rule, the steadier that beat is, the more precise the timekeeping will be.

This sketch shows the key elements of the patented Double Balancier design.


The Double Balancier has two oscillators, each one keeping time independently. The advantage of having two is that their rates can be averaged together to get a more precise measurement. That’s where the Double Balancier’s sophisticated spherical differential gear comes into play. It makes that calculation and then indicates the results on the dial and the sub-seconds display.

In addition, the oscillators themselves have been carefully calibrated to mitigate gravity’s influence. Look closely and you’ll see that both balance wheels are set at a 30-degree incline. Coincidently, the idea for an inclined balance is connected to the company’s award-winning Double Tourbillon 30° — Greubel Forsey’s very first Fundamental Invention.

To improve precision, the spherical differential gear averages together the timekeeping rates from both balance wheels.


The Double Balancier’s cerebral concept is sure to engage horological enthusiasts who relish every mechanical detail. But you don’t need to understand the mechanism’s intricacies to appreciate just how amazing it looks in action. Thanks to the sapphire crystal case, now there’s even more to see.

That was always the intent, explains Stephen Forsey. “We chose sapphire for its exceptional transparency, which allows the collector to enjoy the unique three-dimensional architecture and hand finishing of the movement from all angles. The collector can journey through the timepiece to appreciate its myriad materials and finishes enhanced by the flood of light.”

It takes more than 900 hours to produce each sapphire crystal case.


Turning up the lights puts a sharper focus on the legendary lengths to which the company goes to hand finish every surface and component. Everything has a high-level finish, from the balance wheels and constant differential, to the center bridge. The company’s trademark black-polish finish can be found on the flanks of the escapement platform, as well as the stunning blue dial. Pointing out another key detail, Forsey says, “The words central to the Greubel Forsey philosophy are also engraved around the flanks of the movement itself.”

Even though the company has been using sapphire crystal in its watchmaking for a decade, Forsey says there are still no shortcuts. “We developed our groundbreaking sapphire crystal bridges for the Quadruple Tourbillon in 2008 and made our first sapphire crystal case for the Double Tourbillon Technique in 2016. For the Double Balancier Sapphire, we did not simplify the case shape just to make it easier to machine. It retains the elegant proportions and complex curves of a true Greubel Forsey creation. Even after years of experience working with sapphire crystal, this new case was still a real challenge.”

Greubel Forsey’s watchmaking philosophy is engraved around the flanks of the movement and emblazoned on the inside of the rubber strap.


The delicate and unforgiving process used to make the case begins with a solid block of sapphire crystal. It takes more than 900 hours of milling, machining and polishing until the bezel, case body, caseback and fluted crown are all complete and ready to assemble. The result is sublime.

The Double Balancier is exceptional in many ways. Particularly impressive is how clearly the overall design expresses the symbiotic relationship between its technical and artistic elements. Without a doubt, that shared connection continues to be one of the most important cornerstones of Greubel Forsey’s watchmaking code.


Click here to view the Greubel Forsey collection online at Cellini Jewelers.