The Grönefeld brothers built their name on six-figure watches with lavish hand finishing, the sort of thing that wins prizes and empties wallets. In 2024 they started a second brand, Grøne Oldenzaal, to make something reachable, roughly the move MB&F made when it spun off M.A.D.Editions. The Horologium is the second Grøne, and it is the most conventional thing the family has put its name to. Monochrome covered it on 5 August 2026, with prices and the on-sale date.
A familiar shape at an unfamiliar price
The resemblance to the Grönefeld 1941 Principia is impossible to miss, and Grøne does not try to hide it. The case, the dial layout, the hands and the markers all trace back to it. The Horologium is housed in a 39mm by 10mm stainless steel case with the design cues the brothers use across their work: a polished concave bezel, brushed flanks, downward-curving stepped lugs and a conical crown. It is framed by two sapphire crystals with orange gaskets, a small nod to where it is made, and water resistance is 50 metres.
That is a lot of the Grönefeld look for the money, which raises the obvious question of what it does to the standing of the 1941 Principia above it. The honest answer is that the expensive watch is still the more finely made object, but the gap on the wrist is smaller than the gap on the invoice, and Grøne seems comfortable letting buyers draw their own conclusions.
Two dials, one quiet and one not
The Horologium comes in two tastes. The Quirky is anything but, with a vivid Dutch-orange centre, baby-blue accents on the chapter ring and heat-blued hands, worn on a baby-blue leather strap with orange stitching. The effect is close to a Gulf racing livery. The Classic is the calmer of the pair, a subtly sunray-brushed salmon dial with a matching minute track, silver-toned accents and a dark brown strap. Both share a raised small-seconds plateau, diamond-cut and polished at its rim with a circular-brushed and sandblasted centre, and both carry the same diamond-cut, high-polished indices.
Hand-wound where it usually is not
Behind the now see-through caseback is a hand-wound version of the La Joux-Perret G100. That base is normally sold as an automatic, so winding it by hand is a deliberate choice for a dress watch. It beats at 4Hz, holds about 60 hours of reserve and carries 29 jewels, and it is dressed with Côtes de Genève, diamond-cut bevels and heat-blued screws. The Classic leaves its caseback plain. The Quirky engraves it with a Twents saying, "Zoals het klokje thuis tikt, tikt het nergens," roughly the Dutch equivalent of home sweet home.
Both versions are limited to 188 pieces each. They go on sale from the brand's website on 13 August 2026 at 3PM Amsterdam time, with deliveries expected from mid-September, priced at EUR 2,390 excluding VAT. The pitch is simple enough: the Grönefeld design language and a good deal of the hand finishing, on a watch a lot of people can actually reach. Whether that flatters or undercuts the family's expensive work is a question the brothers seem happy to leave open.
