Monochrome Watches
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Montblanc Goes Deep-Diving with the Iced Sea 0 Oxygen Deep 4810m

Capable of submerging to depths matching Mont Blanc’s height, the muscular Iced Sea diver is prepped for extreme adventures.

| By Rebecca Doulton | 3 min read |

Montblanc introduced its white star logo in 1913, an emblem which has graced the caps of its fountain pens and, later, the crowns of its watches. While the logo is universally recognised, some folk might not know that it represents a stylised bird’s eye view of the snow-capped peak of Mont Blanc and its six glaciers. As a brand that has always fostered its connection to Europe’s highest mountain with a selection of mountaineering-themed sports watches, the decision to introduce a diver’s watch seemed an odd change of direction. However, CEO Laurent’s Lecamp’s gamble paid off with the 1858 Iced Sea, an ISO 6425-compliant, 300m water-resistant diver’s watch with a crackly, sparkling glacier dial inspired by the Mer de Glace or ice sea glacier found on the slopes of Montblanc. Buoyed by the success of the 1858 Iced Sea collection of 2022, Montblanc releases a top-of-the-line diver with an impressive water-resistance of 4,810m, which, as you might have guessed, corresponds to the height of Mont Blanc. Welcome the Montblanc Iced Sea 0 Oxygen Deep 4810m.

Given its superior depth rating, the new Iced Sea model has a larger case with a diameter of 43mm and, mostly, an unmistakable thickness of 19.4mm. To compensate for some of the bulk, the case is crafted in titanium to make it lighter on the wrist. Shielded by solid crown guards, the screw-down, fluted crown displays the signature Montblanc emblem in relief. The powerful 4,810m water-resistant case is decorated with vertical satin brushed finishes and the polished bevel of the lugs accentuates their curved profile.

The professional unidirectional diving bezel, with its deep knurled edge, is made of black anodised aluminium. Given this model’s immersion capacity, luminosity is vital, and the indices and dot at noon on the bezel are treated with blue-emission Super-LumiNova.

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The new Iced Sea 0 Oxygen Deep 4810 forms part of the “Zero Oxygen” timepieces inspired by pioneering mountaineers like Reinhold Messner, who conquered the highest peaks without supplemental oxygen. To honour these intrepid alpinists and equip modern-day adventurers with robust equipment to deal with extreme environments, Montblanc has created oxygen-free cases using a blue seal between the sapphire crystal and the case. Far from a gimmick, removing oxygen means that fogging, which can appear when you move between extreme temperatures, does not build up inside the case. The lack of oxygen – certified by the brand –  also ensures the components will last longer and not oxidise.

Like the earlier 1858 Iced Sea models, the dial features a striated surface reminiscent of the interlocking network of crystals formed over millennia in the Mer de Glace. To achieve this effect, Montblanc uses an old technique known as gratté boisé that relies on a piece of wood to scrape the surface and create delicate scratches. The dial alone takes 30 days to produce. Inspired by the naturally occurring colours of glaciers, the dial has a deep dark blue colour with a sfumato effect.

Bold black Arabic numerals at 12, 6, and 9 o’clock, combined with thick, applied baton markers treated with blue-emission Super-LumiNova, enhance legibility. The cathedral hour and minute hands are also luminous, as is the arrow-shaped tip of the central seconds hand. There is a date window at 3 o’clock, and the dial is protected by a scratch-resistant domed sapphire crystal with an anti-reflective coating.

The caseback reveals another surprise and is decorated with a wavy 3D blue pattern, suggesting the view divers see when plunging deep below the ice. To achieve this swirly metallic blue pattern in relief, the titanium caseback is exposed to laser-generated oxidisation that structures the metal with matte and shiny blue finishes.

Although it is hidden, the automatic MB 29.29 manufacture (ValFleurier, shared with Baume & Mercier, Cartier and Panerai) movement is a powerful, reliable companion capable of delivering up to 5 days / 120 hours of power reserve. In addition to being an ISO 6425-compliant diver, it is also certified as a chronometer by the COSC.

Fitted with an interchangeable strap system, the watch comes with a black, tapered rubber strap that can be adjusted directly on the wrist, even when wearing a wetsuit. The Montblanc Iced Sea 0 Oxygen Deep 4810 will join the regular collection. Price is to be confirmed. For more information, please consult

3 responses

  1. Is it possible, just possible that the Richmont group have embarked on a journey of elevated support towards MONTBLANC?

  2. Thanks for the article!

    It definitely looks like a serious thing! Lovely design and interesting movement.

    I’d say the price will be 1€ per meter of depth + Montblanc extra (≈2k), so… 8,000€ (at least) maybe?

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