The DB25 Starry Varius, in its original form, is one of the most sublime watches ever created by De Bethune. Delectably discreet, it hides all of its horological fireworks – a high-frequency and high-speed tourbillon with a deadbeat seconds – beneath a blued, polished titanium dial that recreates a glorious night sky scattered with stars. The newly launched DB25 Starry Varius Aérolite dials up its celestial magic with a slice of Muonionalusta meteorite, the world’s oldest known meteorite that struck Earth more than one million years BCE.
Composed of mainly iron and nickel, the meteorite in question, when sectioned, reveals a crystalline structure characterized by a 60° angle cross-hatched pattern also known as a Widmannstätten pattern. The dial is first sliced and acid-etched before it is heat treated, resulting in a blue, purply hue that resembles a nebula. A multitude of tiny white gold spheres of varying sizes are then pressed by hand into tiny holes punched into the dial, depicting the stars. They are scattered across the Milky Way, which is the result of a shallow laser engraving that is then covered in 24k gold leaf. The specifics of the constellations can be customized, according to a precise sky map, at a desired date, time and place.
The effect is further amplified when considering the watch’s 42mm case diameter. The case is made of titanium, and though it isn’t rendered in the brand’s signature colour, what makes it special is its resemblance to precious metal thanks to its high polish finish. Inside is the deeply impressive DB2109V4. As with all movements the brand develops, every aspect of the transmission system from mainspring to hairspring has been optimized and protected by patents, making a De Bethune watch mechanically singular, in addition to its inimitable outward appearance.
The DB2109V4 is equipped with two barrels, each fitted with six jewelled blades, arranged like a propeller, on both the upper and low faces of the barrel, to minimise friction of the mainspring against the interior of the barrel. This optimizes energy transmission, simultaneously reducing wear.
Elevated above all else in the movement is the skeletonised, blue titanium bridge that retains a secondary escapement for the deadbeat seconds. It comprises of a pair of solid-gold escape wheels mounted in a co-axial configuration, along with a coiled spring and jewelled pallet. The pallet swings back and forth, releasing the wheels one tooth at a time, advancing the seconds hand in jumps.
Right below the mirror-polished delta-shaped bridge is the high speed and high frequency tourbillon. It contains a balance wheel that oscillates at a frequency of 5Hz, or 36,000 vibrations per hour, which is extraordinarily high for a tourbillon while the cage makes one revolution every 30 seconds, twice the speed of a conventional tourbillon.
This is made possible as the tourbillon has an extremely lightweight construction. The cage and balance are made of titanium while the escape wheel is made of silicon. But in contrast to the escapement where low inertia is favored, timekeeping benefits from a high inertia balance wheel. This is accomplished through its high frequency and at the same time, the titanium balance is further fitted with white gold inserts.
The hairspring, on the other hand, is made of Nivarox, the conventional nickel-iron alloy used for almost all balance springs in watchmaking. However, it is characterized by a very particular terminal curve. In contrast to the traditional Breguet overcoil, De Bethune’s hairspring is flat, but has a wider terminal curve, which reduces its height while enhancing concentricity.
As mentioned at the outset, the De Bethune DB25 Starry Varius is already an extremely compelling watch. But incorporating a rock formed over billions of years ago that traveled across vast distances of interplanetary space to find its home on your wrist adds a lovely bit of poetry to a highly technical watch. In effect, the passage of time is juxtaposed by an eternal backdrop that gives new meaning to De Bethune’s out-of-this-world aesthetics and mechanics.
DB25 Starry Varius Aérolite, Reference: DB25VTM
Case: 42mm by 10.3mm; Polished Grade 5 Titanium
Dial: Star-studded sky in blued and polished meteorite with hand-fitted white gold pins depicting the stars; Milky Way patterns gilded with 24-carat gold leaf; silver-toned hours and minutes ring
Movement: Hand-wound DB2109V4, power reserve of 4 days
Functions: Hour, minutes, dead seconds, tourbillon
Strap: Extra-supple alligator leather with grade 5 titanium pin buckle
Availability: Limited to a production of five pieces per year