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Armin strom sets the tone in the realm of transparent mechanics with the Gravity Equal Force Ultimate Sapphire Purple

MAY 06 2024    |    Novelties

Armin Strom fuses masterful mechanics with a bold chromatic twist, unveiling its latest Ultimate Sapphire Edition. The iconic Gravity Equal Force now sports a striking purple guilloché-engraved mainplate by Kari Voutilainen. 

Armin Strom’s System 78 collection represents the independent manufacture’s purest expression of innovative haute horlogerie. Within it, the classical codes of watchmaking are revisited to bring about new functions and solutions, while also expressing the brand’s unique aesthetic sensibilities. With an emphasis on transparency, as well as highlighting kinetic elements, the Gravity Equal Force stands out as a technical tour-de-force with an instantly recognisable look – outstanding in form and function, finished by meticulous hand decoration. Now, with the new ‘Purple’ Ultimate Sapphire Edition, Armin Strom is doubling down on integrating vibrant chromatic hues with exceptional mechanics.

Let it reign: Gravity Equal Force Purple

At once regal and electric, the latest edition of the Gravity Equal Force features a colour Armin Strom has never used before. Its base plate boasts a guilloché engraved motif with a barley grain pattern, expertly handcrafted in the atelier of acclaimed independent watchmaker Kari Voutilainen using a traditional rose engine lathe. The striking purple colour is applied using a 3D PVD process, which reflects a wide spectrum of tones as it shifts with the light. Making this edition even more outstanding, the small off-centred dial is crafted from transparent sapphire crystal, which is reserved exclusively for the Gravity Equal Force’s Ultimate Sapphire Editions. The crowning glory is a light grey nubuck leather strap with purple stitching and keepers. The Gravity Equal Force Ultimate Sapphire Purple is limited to a run of 25 pieces per year.

 

Automatic: redefined

The Gravity Equal Force stands out as the first automatic watch endowed with an equal force transmission integrated directly in the mainspring barrel - a patented mechanism by Armin Strom. It provides consistent power transmission to the regulating organ, ensuring unwavering precision throughout the watch’s autonomy. The power reserve indicator forms part of the barrel, which is entirely visible from the dial side, opposite the micro-rotor with a unique click system featuring two springs for better winding efficiency.

Also this latest creation, part of Armin Strom’s perpetual quest for superior chronometric performance, was entirely developed, manufactured and decorated within the walls of the Bienne-based manufacturing site. Like all Armin Strom watches, the Gravity Equal Force Purple’s movement is assembled a first time to ensure it is in perfect working order and that it meets the brand’s exacting decorative standards, then taken apart and assembled a second time when it is ready to be cased in its final form. 

 

Putting the ‘haute’ in ‘horlogerie’

What separates a mere tool from a work of art is craftsmanship. Like a canvas for artistic expression, superlative hand-finishing applied by specialised watchmakers and seasoned artisans can be appreciated throughout the Gravity Equal Force and its many proudly exposed layers and components. Polished bevels (anglage) on the bridges, black polished screws, polished countersinks, perlage and various types of graining, be it straight or circular, as well as Geneva stripes on the three-quarter bridge visible through the case’s back.

One of the Gravity Equal Force’s most distinctive elements is the triplet of dark grey ruthenium-plated bridges that occupy the right-hand portion of the open display. Inspired by the finger-style bridges found in pocket watches, it takes up to an entire day for these bridges to be embellished by hand. First, the undersides are given a matt finish, after which the sides are given a straight-graining finish by carefully sliding them on an abrasive paper to produce continuous, shimmering fine lines. Then, the inner and outer chamfers of the bridges are bevelled with increasingly fine files and then finished with a flash polish using locally sourced gentian wood to remove even the finest lines. Finally, a straight-graining finish is applied to the top side for ultimate radiance.

Armin Strom : 15 years in the science of movement

In 2008, longtime friends and partners Serge Michel and Claude Greisler took the reins at Armin Strom and founded its very own manufacture in the watchmaking town of Biel in 2009. Just one year later, the duo presented their very first watch with a movement designed and manufactured in-house. Over the following years, Armin Strom would become a truly integrated and self-sufficient manufacture, creating 17 exclusive calibres and developing several world firsts in the domain of watchmaking. In 2016, it introduced the Mirrored Force Resonance, a game-changing resonating dual regulator developed for maximum chronometric precision with a captivating oscillation mechanism on the dial-side of the watch. In 2019, Armin Strom reinvented the automatic watch movement with the Gravity Equal Force, the first automatic watch to feature an equal force transmission mechanism within the barrel that had previously been found only in pocket watches. Today, Armin Strom stands out as a leading force of creative, independent watchmaking, with its own distinct design language and exceptional attention to detail highlighted by hand-finishing all its creations. 2024 promises to be a year full of surprises, and the best is yet to come…

 

Gravity Equal Force Ultimate Sapphire Purple

Technical specifications

                   

Indications     Hours, minutes, seconds, power reserve indicator
Movement     Armin Strom manufacture Caliber ASB19
      Automatic winding with micro rotor, Geneva-drive equal force barrel, offset display with subdial seconds
Main plate   purple PVD plate with guilloché pattern by Kari Voutilainen
Regulating system   Balance wheel with 4 regulating screws
Power reserve   Geneva stop-work limited to 72 hours
Dimensions   35.52 mm x 11.67 mm
Frequency   3,5 Hz (25,200 vph)
Finishing   Hand-finishing to the highest quality level
Jewels   28
Number of components   202
Case   stainless steel
    Sapphire crystal and case back with anti-reflective treatment
Diameter   41 mm
Height   12.65 mm
Water resistance   3ATM
Lug-to-Lug   48.09 mm
     

Dial

 

Grey toned off-center sapphire dial with subdial

Hands  

Faceted polished hands and Super-LumiNova® filling

Strap   Delivered with a grey nubuck leather strap with purple stitching and keepers
Width lugs/buckle   20/18 mm
Buckle   Pin buckle or folding clasp available in stainless
Reference   ST24-GEF.SA.AC.M.A7.FC
Limited production   25 pieces per year

 

 

                                           

                                            

 


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C BY ROMAIN GAUTHIER 39.5: BUILT FOR EVERYDAY ELEGANCE

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Enhancing this newfound versatility, the manufacture introduces its very first interchangeable rubber strap system alongside three expressive new colorways: vibrant blue, energetic orange, and subtle pink. These eye-catching color accents on the dial are matched with corresponding Super-LumiNova hues at night, offering a fresh, lifestyle-oriented aesthetic. The quick-release strap system allows wearers to effortlessly adapt the watch to any mood, outfit, or occasion, transitioning seamlessly between sporty casualness and discreet, refined elegance.

While the exterior boasts a contemporary, relaxed style, the heart of the watch remains deeply committed to haute horlogerie. The in-house manual-winding caliber is gloriously on show through the display back, showcasing finger bridges—historically typical of Romain Gauthier’s birthplace, the Vallée de Joux—reinterpreted with a modern "stepped" architecture. Each Grade 5 titanium bridge is meticulously finished by hand, featuring a highly original dimpled texture achieved through a special hand-engraving technique, set against a beautifully hand-frosted movement mainplate.

Technically astute, the timepiece is equipped with a clever stop-seconds mechanism that uses a snail cam—a nod to the brand’s acclaimed Logical One. Pulling out the crown stops the balance wheel, while pushing it back in prompts the snail cam to turn, delivering an active impulse to help the movement start beating again instantly. Offered as part of the brand's permanent, non-limited collection, the C by Romain Gauthier Titanium Edition 39.5 represents a masterful synthesis of superlative hand-finishing and modern, adaptable luxury.

 

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Arnold & Son Perpetual Moon 41.5 Red Gold – Cliff Grey Edition

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The dial is adorned with the exclusive Stellar Rays motif, a textured pattern that plays with light through layered transparent lacquer. Its Cliff Grey tone evokes the misty British coastline, while the moon phase display—among the largest in watchmaking—glows in mother-of-pearl enhanced with Super-LumiNova. Set against a midnight-blue sky, the moon is surrounded by hand-painted constellations, Ursa Major and Cassiopeia, symbols of guidance and exploration.

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Inside, the manually wound A&S1512 calibre offers a 90-hour power reserve and tracks lunar cycles with remarkable precision. So accurate is its mechanism that it would take 122 years of continuous operation to accumulate a single day’s deviation from the actual lunar cycle.

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Introducing the Armin Strom Gravity Equal Force Ultimate Sapphire Blue

We are thrilled to announce the launch of the Armin Strom Gravity Equal Force Ultimate Sapphire Blue, a masterpiece of Swiss horology that combines technical innovation with glacial elegance.

Design & Aesthetics

The watch features a 41 mm stainless steel case and an off-center transparent sapphire crystal dial with a subdial. The main plate, crafted by Kari Voutilainen, showcases a stunning glacial blue guilloché pattern. The color palette of silvery greys and soft blues is inspired by the serene beauty of Swiss glacial lakes. The watch is completed with a blue nubuck leather strap with ice blue stitching.

Movement & Mechanics

Powered by the proprietary Caliber ASB19, the Gravity Equal Force Ultimate Sapphire Blue is the world’s first automatic movement with a patented stop-work declutch mechanism and Geneva cross. This ensures consistent torque and precision across a 72-hour power reserve. The movement is visible through both the front and back sapphire crystals, and features hand-finished components with perlage, Geneva stripes, and circular graining.

Craftsmanship

Each watch is assembled twice to ensure reliability and refinement. Every component is hand-finished in Biel/Bienne, emphasizing traditional techniques and an open-worked design.

Brand Philosophy

Armin Strom celebrates Swiss horological tradition and innovation. Founded in 1967 and revitalized in 2009 by Claude Greisler and Serge Michel, the brand is known for exposing movement mechanics on the dial side. Their motto, “The Science of Movement,” reflects their dedication to precision and craftsmanship.

Limited Edition

The Gravity Equal Force Ultimate Sapphire Blue is limited to just 25 pieces per year, making it a truly exclusive timepiece.
 

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A Deeper Cut: Armin Strom One Week Skeleton Rose Gold

   

Armin Strom extends its golden era with the One Week Skeleton Rose Gold, a new interpretation of its architectural One Week design. This fully skeletonised masterpiece reveals the depths of its mechanics, paying tribute to Mr. Armin Strom’s pioneering artistry in skeletonisation—a craft at the heart of the brand’s philosophy and heritage.

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Transparency in Gold
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