The 10-piece Decennium Tourbillon, while a celebration of the Grönefeld brothers’ decade as an independent, was a disciplined execution that encompasses their past and a view of their future. Framed within proportions it shares with the 1941 Remontoire, it features a tourbillon and a self-winding calibre. This is paired with the superlative finishing that is the brand’s hallmark.
The familiar 1941 Remontoire case, measuring 39.5mm across is crafted from platinum and cleverly designed to minimise its footprint and toy with light. This is evident in the concave form of the bezel, that in the Decennium Tourbillon features an additional detail – it has a stepped, wave-like crease at 12, with this detail mirrored at 6 o’clock as well.
The short but substantial lugs have a flowing form, scalloped out to repeat the concavity of the bezel. Such sculpting is evident even in profile where the sharply concave lug profiles, contrasting against the rounded midcase, serve to minimise the already conversative 10.5mm case height. The play of surfaces, going from concave to convex details, makes the case glimmer.
The deep knurled crown, which brings to mind jet exhausts, is signed. The lugs, 20mm apart, are fitted with a fresh grey, quick-release leather strap with contrast blue stitching. It is secured with a signed platinum pin buckle.
The steel-grey lacquered finish on the sterling silver dial, with its blue undertones, is complemented by the dark blue pad printed brand and line marks and the minutes chapter. This blue is repeated in the lancet hands, that are beautifully curved and heat hued.
The faceted hour markers are black polished, as is the stepped circular sector and the one that frames the tourbillon. Like the case, these glimmer giving the dial an attractive brilliance.
Similar attention is lavished on the finish of the one-minute tourbillon. Pivoting on ball bearings, the cage is anchored on the dial side by a rounded bridge that is blacked polished at the top and vertically brushed at the base where it is screwed onto the carriage. The escape wheel and pallet fork are black polished as well. The rim of the cage and the bridge anchoring the escapement and pallet fork feature beautiful anglage. The balance wheel features four white gold timing screws and a hairspring with Phillips terminal overcoil curve.
It is paired with the calibre G-07, reserved just for this 10-piece series. Visible through the display caseback, it features the familiar stainless-steel gable-shaped bridges reminiscent of the roofs of Dutch houses. These bridges wear micro-blasting in the centre, with raised, hand-bevelled edges. They are topped by a full-sized solid 22k gold unidirectional winding rotor finished in a similar way to the bridges underneath. The rotor has a wide bevel that is black polished. A semi-openwork horse-shoe bridge runs the arc from the winding barrel to the keyless works and is black polished to perfection. Through it the circular-grained, ruthenium-plated brass baseplate is visible.
The bridge anchoring the barrel is laser engraved with the commemorative message celebrating the brand’s 10th year while the one at 12 o’clock features the serial number out of 10. The calibre G-07 features 259 parts and 30 jewels. It extracts 56 hours of reserve from its single mainspring barrel.
The set includes all original paperwork as well as the outer and leather inner boxes and the Barnard Favre double-axis winder the Decennium Tourbillon retailed with. As celebrations go, this is perhaps one of the most considered and rooted in recent memory. Technically impressive and lushly decorated, it is a watch that honours the past Grönefeld mines while decidedly modern in its execution.
