URWERK UR-101 Diamond Sky Watch Review
While the URWERK UR-101 Diamond Sky shares some characteristics in common with its antecedents, it looks surprisingly different courtesy of its structural use of diamonds. Indeed, as Meehna Goldsmith explains, this new model is not a watch adorned with diamonds but rather a celestial object engineered for the wrist.
URWERK – party people
Anyone who hangs out with those in the watch industry knows that they’re a group that likes to party. And, it’s a good thing they do. Without a fateful meeting at a New Year’s shindig in 1995, the URWERK brand might not have come into existence. During that evening, brothers and watchmakers Felix Baumgartner and Thomas Baumgartner, along with designer Martin Frei, met. Somewhere between the music and late-night philosophising, they began discussing how time itself could be expressed differently. By the first morning of 1996, the idea for URWERK had crystallised, followed just a year later in 1997 with the debut of the UR-101 and UR-102.
Papal clocks and the Campani brothers
The watchmaking Baumgartner brothers and designer Frei weren’t interested in rehashing traditional models of telling time. That wasn’t interesting or challenging enough. They wanted to reinterpret the passage of time through Haute Horlogerie craftsmanship fused with cutting-edge mechanics. Ironically, the three were inspired by a pope with insomnia and the Roman inventors who solved his problem – all in the 17th century.
The year was 1682 and the newly appointed Pope Innocent XI just couldn’t get enough shuteye. The clock in his bedchamber was too noisy and kept waking him up with its tick-tock sound. If that wasn’t annoying enough, after being jarred awake, the nervous pope couldn’t even see what time it was in the dark.
Enter the Campani brothers, who were commissioned to make a night clock for the pontiff, with Pietro Tommaso inventing the silent escapement and replacing the loud verge mechanism. If the mechanics weren’t impressive enough, the brothers also came up with an innovative display with transparent hour numerals travelling along a semi-circular arc that delineated the minutes. Once the hour traversed to the right side of the arc, the next hour would come up on the opposite side, much like the sun traversing a horizon. An oil lamp inside the wooden clock case illuminated the hour display, providing the Pope with the capacity to view time in the dark.
URWERK UR-101 & UR-102 – Baselworld 1997
When URWERK showcased the UR-101 and UR-102 at Baselworld in 1997, the pieces stood out from the usual suspects. Experimenting with time displays, case shapes and mechanisms isn’t unusual now, but it was back then. The Harry Winston Opus collection, Greubel Forsey and Devon Timepieces, to name a few, weren’t even a blip on the radar yet. It was URWERK that ushered in the new wave of experimentation and the melding of Haute Horlogerie finishing techniques with avant-garde mechanics.
URWERK UR-101 Diamond Sky – ‘extending an intuition’
With the case inspired by the Millennium Falcon, satellite display, crown at 12 o’clock and angular lugs, the UR-101 Diamond Sky maintains all the defining characteristics of the original.
“The UR-101 is our starting point,” explains URWERK co-founder and master-watchmaker Felix Baumgartner. “It contains everything that has become emblematic of URWERK: the satellite display, time’s motion expressed as a path, along with the desire to offer a dial representing a break with traditional norms.” Baumgartner continues, “We are not looking back with this Diamond Sky edition, but instead extending an intuition.”
Last year, URWERK revisited the foundational UR-101 with the UR-101 T-Rex, a limited edition of 100 pieces featuring the wandering hours display housed in a tactile bronze case that resembles the scales of a dinosaur. The UR-101 now gets the glow-up treatment with the Diamond Sky. It marks the first time URWERK has united the mechanics and gemstones in such a way, albeit it’s not the brand’s first jewellery watch. Indeed, who could forget the gorgeous UR-106 Flower Power, released in 2017?
URWERK UR-101 Diamond Sky – an abstract constellation
At a distance, the 41 mm stainless steel Diamond Sky case is meant to resemble an abstract constellation from the engraved geometric network. At each cross-section, a diamond flashes like a fixed star in a dynamic universe. More than decorative, the effect is structural, an integrated whole as diamond light skims and dances with each turn of the wrist. “[The diamonds’] hexagonal arrangement follows a clear principle: in space, stars bear witness to the laws of nature,” says Frei. “On our dial, they create balance, connecting top and bottom, and translate a design vision into a simple, harmonious structure.”
Inside the Diamond Sky lives the UR-1.01V, a self-winding calibre with a 48-hour power reserve. Haute Horlogerie finishing techniques include snailing, sandblasting, satin-brushing and chamfering of screw heads. To improve legibility, the wandering hours and minutes markers are painted with Super-LumiNova. The watch is presented on a textured white rubber strap, lined in black calfskin, and secures to the wrist with a steel pin buckle.
Closing remarks
With the Diamond Sky, URWERK keeps its edge while adding shimmer to the rebellion. The result feels less like a watch adorned with diamonds and more like a celestial object engineered for the wrist.
Further reading
Technical specifications
- Model: URWERK UR-101 Diamond Sky
- Case: steel set with 214 D-E-F VVS+ responsibly sourced diamonds totalling 1.63 carats
- Dimensions: 41 mm in diameter, 9.33 mm thick
- Functions: wandering hours on two satellites, minutes
- Movement: Calibre UR-1.01V, automatic movement, frequency 28,800 vph (4 Hz), 28 jewels, power reserve 48 hours
- Strap: textured white rubber with black calfskin lining paired with a steel pin buckle
- Price: CHF 85,000 excluding taxes (RRP as of 13.5.2026)