Jaeger-LeCoultre Launches Geophysic True Second Limited Edition in Ocean Blue

Jaeger-LeCoultre’s Geophysic collection, which sprang from 2014’s single, limited-edition Geophysic 1958 model, continues to grow, as the Le Sentier-based manufacture introduces a new, online-boutique-exclusive version of its Geophysic True Second model with a striking, ocean blue dial.

Jaeger-LeCoultre Geophysic True Second LE - flat

First, a bit of background on the Geophysic: Jaeger-LeCoultre released the original model with that name in 1958, the designated “International Geophysical Year” in which 67 nations from the East and West cooperated, during the height of the Cold War, to undertake a series of scientific explorations of the planet’s unexplored regions. The watch was designed to be a companion on these expeditions, many of which took researchers to harsh terrains and climates, so it utilized the era’s most advanced watchmaking technology. Its manual-wound movement, Caliber 478BWSbr, was derived from military watches and included a stop-seconds function for precise timekeeping; a Glucydur balance with shock absorption for stability through extreme temperature changes; and a swan’s neck index for adjustments. The watch’s most essential component was the soft-iron inner case that protected the movement from the effects of magnetism. The Jaeger-LeCoultre Geophysic accompanied the crew on the U.S.S. Nautilus, the first-ever atomic submersible vessel, on its record-setting expedition beneath the North Pole on August 1, 1958, the first submerged transit from one ocean to another via the Arctic ice sheet. The watch’s role in this event has made it one of the vintage Jaeger-LeCoultre watches most prized by collectors — and thus the inspiration for the modern collection, whose most recent edition was a tourbillon with a world-time function, introduced at SIHH 2017.

Jaeger-LeCoultre Geophysic True Second LE - reclining

The new timepiece, which is limited to 100 pieces, comes from the Geophysic True Second family, which debuted in 2015 with rose-gold and steel cases and silver-toned, grained dials — and is the first model with the new ocean-blue, sunburst-finish dial. Like the 1958 model, the dial has in its center a crosshairs motif that calls to mind location-mapping instruments. Like its more recent predecessors, the watch has a 39.6-mm-diameter case, here in stainless steel, with lugs that meet the case middle not with a smooth curve but with a sharply defined angle, an expression of this model’s tool-watch heritage. The sides are polished to accentuate their silhouette and the bezel slightly overlaps the case and lugs, making for a streamlined look. The screwed-in caseback also echoes that of the watch’s historical predecessor, ensuring a respectable water resistance of 50 meters, and the inner part of the case middle, surrounding the dial, features the vintage-inspired Super-LumiNova-filled “dots,” corresponding with the dial’s applied, linear hour markers, that enable the wearer to read the time easily in the dark. The triple-faceted hands are also coated with the luminous material.

Jaeger-LeCoultre Geophysic True Second - Wrist

The dial’s clean, simple look belies the complexity of its in-house movement, Caliber 770, which represents a technological milestone for the brand. It features an atypical, non-circular balance wheel called a Gyrolab, a device whose main attribute is the reduction of air friction to ensure greater timekeeping precision, as well as the technical element from which the watch derives its name — its “true seconds” (known more commonly as “dead-beat seconds”) feature, which causes the seconds hand to jump forward once every second, a rarity in a mechanical watch and one that enables a much more precise reading of the seconds. This function is, again, a nod to the original Geophysic’s role as an authentic, time-measuring instrument for scientific research. The rotor in this self-winding caliber is crafted from a single block of solid gold and shaped in the “anchor” motif that echoes both the shape of the movement’s escapement lever and the Jaeger-LeCoultre logo. The rotor is openworked to allow a more unobstructed view of the movement, whose  bridges are decorated with côtes de Genève. Each caliber undergoes JLC’s rigorous and exclusive “1,000 Hours Control” testing (details on which here) for reliability and precision.


Jaeger-LeCoultre Geophysic True Second LE - back


Engraved on the periphery of the exhibition caseback with its limited edition number (xx/100) and mounted on a brown calfskin strap with a patina finish, this Jaeger-LeCoultre Geophysic True Second model is available exclusively at Jaeger-LeCoultre’s online boutique at

Jaeger-LeCoultre Geophysic True Second LE - front
Leave a Reply