With the Jaeger LeCoultre Geophysic hitting boutiques and retailers around the country, we thought it would be a good opportunity to highlight a long forgotten JLC reference released in 1958, the same year as the original Geophysic. The Jaeger LeCoultre Master Mariner Chronometer kicked off a line of watches in the American market that would eventually bring on their first dive watches in the ‘60s. Resources are rather scarce on this particular reference, so we’d like to thank Nicolas (amanico) from the JLC WatchProSite forums for tracking down valuable information.
1958 JLC ad clearly taking aim at seafaring types
Despite the lack of information available now, it seems that the Master Mariner Chronometer appeared in a number of advertisements in the late 1950s. In addition to celebrating their 125th anniversary, JLC clearly attempted to market them towards seafaring types, as the ads featured pictures of, and quotes from, ship captains. While we can’t confirm the degree of water resistance, having a chronometer grade movement would have served ship captains well. Besides, if a ship captain of a major vessel is in the water, telling the time is probably the least of his worries.
1958 JLC ad with a handwritten letter from a ship captain about the MM Chronometer
The Master Mariner Chronometer has decidedly dressy looks, but very much in line with the majority of watches from its day. Featuring a thin, 18k gold case, less than 10mm thick, and 36mm wide, the dimensions are pretty much what you would expect from a mid-20th century timepiece. An interesting design choice was with the sharp, but obtuse bevel bisecting the front-facing side of the long-ish lugs. The length of the lugs likely would help the watch wear a bit bigger, and the bevel belied the otherwise dressy appearance, but in a good way. From what we can see in the limited pictures available, the Master Mariner Chronometer came in at least two dial configurations, differing by the 3-6-9-12 hour markers. One configuration seen has numbers, and the other has applied diamond shaped markers. The numbers definitely add a bit more sportiness to the overall look, like a fancied-up Rolex Explorer ref 1016.
JLC Master Mariner Chronometer w/ caliber 476/3 — all pictures courtesy of JLC WatchProSite user Amanico
When it comes to JLC timepieces, it’s typically what’s inside that gets watch geeks all — well — geeky. The MM Chronometer houses the caliber 476/3, a descendent of JLC’s first automatic caliber, the 476. If it had the same caliber as the Geophysic, we would have either heard more about the early MM Chronometers already, or it would be one of the best-kept secrets in vintage collecting. However, being tied to their first automatic is still a cool back story. The non-hacking, bumper automatic beating at 18,000 bph must have been reliable and accurate, given the chronometer certification, and the gushing support from at least one ship captain (although it could have been scripted by Don Draper).
Jaeger LeCoultre is already not talked about enough, so when we found out about an early, obscure sport reference, largely overshadowed by another, we had to write about it. The Master Mariner Chronometer ticks all the vintage boxes, and it’s one worth keeping an eye out for. You’ll have to look hard, but given its under-the-radar profile, it could be a great pickup.
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