The history of this Montblanc 1858 Geosphere
The Montblanc Maison pays a strong tribute to the golden age of mountain exploration with this model. A direct heir to the precision instruments crafted by the Minerva manufacture during the 1920s and 1930s, this piece was designed to face extreme environments while maintaining optimal legibility. Reference 117840 follows this lineage by introducing a particularly innovative world-time complication. Rather than a traditional city-disc display, it integrates two rotating three-dimensional domes representing the northern and southern hemispheres. The most captivating detail of this dial lies in the presence of tiny red dots marking the exact location of the seven highest summits on each continent. This discreet addition transforms the instrument into a genuine expedition map dedicated to the most demanding alpine challenge of our time.
Case, calibre and bracelet of this 1858 Geosphere
The 42-millimetre case with a thickness of 12.8 millimetres is machined from a specific bronze alloy. This material has the unique characteristic of developing an oxidised patina over time according to the adventures of its wearer. The bidirectional rotating bezel is topped with a black ceramic insert engraved with cardinal points. Beneath the domed sapphire crystal, the deep black dial creates a powerful contrast with the Arabic numerals and cathedral-shaped hands coated with beige luminescent material. The self-winding mechanical calibre MB 29.25 powers this piece. It features 26 jewels, beats at a frequency of 28,800 vibrations per hour and delivers a 42-hour power reserve. This mechanism drives the two rotating globe complications completing a full rotation every 24 hours with day and night indication, a second time zone positioned at 9 o’clock and a date display at 3 o’clock. The solid titanium caseback is laser-engraved with the Mont Blanc massif to ensure hypoallergenic comfort and guarantees water resistance tested to 100 metres. The ensemble is fitted with a cognac brown aged calfskin Bund-style strap secured by a bronze-coated pin buckle.
Why this Montblanc watch
The appeal of this edition lies in its rarity and assertive concept. Limited to only 1858 pieces worldwide, it represents a highly sought-after opportunity on the pre-owned market. The combination of bronze and the hemispherical world-time complication offers a remarkable balance between vintage aesthetics and genuine mechanical complexity. This model is no longer available in official boutiques, which further strengthens its appeal among enthusiasts of exploration watchmaking.
Delivered contents and condition
This timepiece is delivered with its original presentation box, outer box, instruction manuals and Montblanc warranty card. The ensemble reveals a very good overall condition with a naturally even patina already developing across the bronze case. The leather strap displays slight signs of wear testifying to careful use without affecting its robustness. Although patina forms an integral part of the spirit of a bronze piece, our watchmakers may carry out a cleaning or polishing service upon request to restore the metal’s original brilliance.
Warranty and delivery
The Swiss Collector guarantees the authenticity of this piece. The watch is covered by a 24-month warranty. We accept returns within 10 days according to our conditions. Leader in pre-owned luxury in Switzerland and backed by the largest network of boutiques, we offer online reservation for an in-store fitting and collection or fully secured international shipping.
* Very good condition – watch previously worn and polished. Light external signs of wear. Case and bracelet in excellent overall condition.
