By: Roger Ruegger
In 1962, Rado wanted to create a watch so durable that it would not only las for a lifetime, but also remain without scratches. To do so, Rado first had to find an ultra-resistant material for the case: Tungsten carbide. The material contains equal parts of tungsten and carbon atoms. In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes through sintering. During this process, the metal liquefies, and the part obtains its final density and hardness and shrinks. The surfaces are then mechanically machined.
“This is how it all began at Rado in 1962 in terms of high-tech materials. Hardmetal is a composite material consisting of a ceramic – tungsten carbide – and a metal binder. The excellent mechanical properties of this compound combine the extreme hardness of the ceramic with the high toughness of the metal.”
In short, tungsten carbide is approximately three times as stiff and twice as dense as steel. It is comparable with corundum in hardness, approaching that of diamond.
Modern Diastar watches feature a case made of stainless steel with a bezel made of what Rado calls Ceramos: it combines the hardness properties of ceramics (around 90 % titanium carbide) with the toughness and lustre of a metal alloy. According to the Swiss watchmaker, “Ceramos is a further development of hardmetal: it offers an improved scratch-resistance and has significantly lower specific weight.” Rado used it for the first time in 1993 when the Rado Sintra product line was introduced, where it was pressed. In 2011, Rado developed a technology to make this material injectable. Ceramos was already used for the Diastar Original on the occasion of its redesign in 2022, and the latest three versions also feature a 38-mm Ceramos bezel with a square-faceted sapphire crystal. All three are limited to 555 pieces each (and are not individually numbered), the green option comes with a PVD-coating on the case.
The blue and red options (Ref. R12169209 and R12169409) are powered by a skeletonized, rhodium-coloured Rado R808 automatic movement, with a horizontal brushed finish, the green and slightly more expensive version (Ref. R12166309) is powered by a yellow gold-colored execution of the movement, all offering a power reserve of 80 hours.
Hit the play button to see the three watches in action:
Diastar Original Skeleton Limited Edition
Dimensions: ⌀ 38 mm (thickness: 11.9 mm)
Case: stainless steel with a Ceramos bezel on top
Water Resistance: 100 m
Movement: R808 with 80 hours of power reserve
Strap: rubber with pin buckle
Warranty: 60 months
Price: from CHF 2,150/€2,500/$2,550 (Ref. R12169209 and R12169409) to CHF 2,400/€2,750/$2,800 (Ref. R12166309)
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