By Brent Robillard
Manhole Covers of the World
I have come to expect the unexpected from Isotope. Every time I speak with co-founder José Miranda, or spend time with one of his watches, I am reminded that this is a brand comfortable operating just outside the usual lines. Inspiration tends to come from places most of us would overlook—film, typography, everyday objects—and yet the end result almost always feels cohesive within the broader Isotope catalogue. The Mercury platform, in particular, has proven to be an ideal canvas for this kind of experimentation, adapting with ease to ideas that might feel out of place elsewhere.
The latest release, the Altmann × Isotope Osaka Cloisonné Enamel, may be one of the more unusual starting points yet. The watch takes its cues from Japanese manhole covers—specifically a municipal design from Osaka—and translates that visual language into a cloisonné enamel dial. It is the sort of concept that sounds improbable at first, but makes more sense the longer you sit with it. Japanese manhole covers are, after all, known for their intricate graphics and strong sense of local identity. Bringing that into watchmaking feels like a continuation of an existing design tradition.
Björn Altmann
The collaboration itself comes by way of Björn Altmann, a designer and illustrator whose book Manhole Covers of the World served as the initial spark. A conversation between Altmann and Miranda led to a project that blends documentation and reinterpretation—Altmann’s study of these urban objects paired with Isotope’s experience in producing unconventional dials. The chosen Osaka design centres on Osaka Castle, framed by flowing water motifs and cherry blossoms. It is detailed, balanced, and, importantly, left largely intact in the transition from infrastructure to wristwatch.
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Key Features of the Isotope x Altmann Osaka Cloisonné Enamel
Dial design
What stands out here is the decision not to simplify the design. Instead, the brand has leaned into its complexity, which is where the cloisonné work becomes essential. Each dial is built on a sterling silver base, with fine wires forming the outlines of the design before layers of enamel are applied and fired repeatedly in a kiln. The process is slow and unforgiving. Each colour requires its own firing, and the dial must be built up gradually to achieve the desired depth and surface. In this case, that meant nearly a year of development before production began.
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A collector’s piece
The Mercury platform
Underneath the dial, the watch is built on familiar ground. The Mercury platform remains compact and wearable at 38mm in diameter and 10mm thick, with a 44.5mm lug-to-lug measurement. The stainless steel case is paired with a domed sapphire crystal and an exhibition caseback, offering 100 metres of water resistance. Inside is the manually wound calibre I-7, a modified ETA Peseux 7001, beating at 21,600 vibrations per hour with a 42-hour power reserve. It is a sensible and proven movement choice, one that keeps the focus where it belongs—on the dial.
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Limited Edition
Availability reflects the scale of the project. The Altmann × Isotope Osaka Cloisonné Enamel is limited to five pieces, each delivered with a signed copy of Altmann’s book. The watches become available today, March 24, 2026, at 3:00 PM GMT, and are ready to ship. Pricing is set at £3,600 plus VAT on strap, or £3,800 plus VAT with an additional bracelet.
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Final Thoughts
Stepping back, what continues to impress me about Isotope is not just the willingness to pursue unusual ideas, but the discipline to execute them properly. It would be easy for a concept like this to feel gimmicky. Instead, it reads as considered and technically ambitious, grounded in a genuine appreciation for design in its many forms. The Mercury platform, once again, proves capable of carrying that weight—and of adapting to yet another unexpected direction.
Miranda’s ability to pull inspiration from the everyday—here, a Japanese manhole cover—calls to mind the way Warhol once reframed ordinary objects, though the result here is grounded more in craft than commentary.
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About the Author
Brent Robillard is a writer, educator, craftsman, and watch enthusiast. He is the author of four novels. You can follow him on Instagram.
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