Monochrome Watches
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The Omega Speedmaster Moonwatch 321 Platinum

The renaissance of legendary calibre 321 on board a majestic platinum vessel complete with lunar meteorite.

| By Rebecca Doulton | 6 min read |
Omega Speedmaster Moonwatch 321 Platinum 311.

Omega’s Speedmaster Moonwatch has exerted its gravitational pull on earthlings for over half a century converting Omega’s robust chronograph into a living icon. For countless fans of the Speedmaster, Omega’s announcement in 2019 that it would be resuscitating its legendary Calibre 321 was as exciting as the Moon landing. The first watch graced with the revered hand-wound column-wheel chronograph was the high-end Speedmaster Moonwatch 321 Platinum followed a year later by a steel model, the Moonwatch Calibre 321 (which we named “The Ultimate Speedmaster”). Let’s take a closer look at this heavyweight deluxe version with its onyx dial and lunar meteorite counters.

Omega Speedmaster Moonwatch 321 Platinum 311.

What came first, the chicken or the egg?

Before the Speedmaster even existed, its heart was already beating at Lemania’s manufacture in Villeret. Renowned for its outstanding watch movements, in particular chronographs, stopwatches and repeaters, Lemania once provided chronograph calibres for the big names in watchmaking. In 1941, Lemania produced the 27 CHRO C12, the ancestor of Omega’s calibre 321 that was, and still is, recognised as one the best and most beautiful hand-wound chronograph movements ever produced.

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The original Calibre 321, as found in all Speedmaster watches until the introduction of the calibre 861 in 1968

The first Speedmaster of 1957, with its distinctive tachymetre scale placed on the bezel, was fitted with this calibre although other Omega chronographs, like those in the Seamaster collection, were also recipients of the movement. Based on the Lemania ébauche, Omega’s calibre 321 equipped the Speedmaster from its creation in 1957 (in the CK2915) until the end of the 1960s with the launch of the calibre 861. Based on a column-wheel and horizontal clutch architecture, the Calibre 321 is regarded as a more prestigious, more “horological” movement than the ultra-robust but simpler calibre 861 used between 1968 and 1996.

Omega Speedmaster Moonwatch 321 Platinum 311.
The “new” historic re-creation of the Calibre 321

The calibre 321 saw plenty of action in space: it was the movement ticking inside Wally Schirra’s personal watch (CK2998) used during the 1962 Sigma 7 Mission marking the first ‘unofficial’ Speedmaster in space; in 1965 it was tested and qualified by NASA for all space missions and worn by astronaut Ed White (ST105.003) during the first American spacewalk, and it was also onboard the Speedmaster (ST 105.012), the first watch worn on the Moon. If you are interested in the nitty-gritty details of the Speedmaster’s evolution, we recommend this guide with an identikit of the many references.

Moon rocks and metals

The choice of platinum (which is about 60% heavier than gold) adds a luxurious and reassuring heftiness to the case. After all, NASA officials have indicated that we could be mining platinum on the Moon in the very near future. For the Speedmaster Moonwatch 321, Omega has used a special platinum alloy with gold (Pt950Au20). The case design is similar to the more robust case of the ST105.012 Moonwatch, with its protective buttresses to shield the pusher and crown and the twisted lyre lugs. Measuring 42mm across, the platinum case features brushed and polished finishings (it’s worth remembering, though, that platinum is easily scratched). The hallmark tachymetre bezel is made of black ceramic with white enamel markings for a crisp contrast. Thanks to the column-wheel construction of the chronograph, the activation of the pushers is super-smooth.

Omega Speedmaster Moonwatch 321 Platinum 311.

The inky black dial is made from onyx and borrows a design feature we normally associate with Omega’s early Speedmaster models, namely the step dial construction. To be more exact, a raised central area and a slight slope on the periphery, which was found in most watches from about 1961 to 1974. The rich black lustre of the onyx sets the stage for the three sub-dials made with slices of mottled grey lunar meteorite. White gold is used for the hour and minute hands and the applied indices, all treated with Super-LumiNova. Fans will appreciate the inclusion of the applied vintage Omega logo and the inscription “Professional” at noon along with the “dot-over-90” on the tachymeter scale like the original ST 105.012, the last Speedmaster to host the calibre 321 and the first to include the Professional inscription.

Omega Speedmaster Moonwatch 321 Platinum 311.

Looking at this Platinum edition now that the new Speedmaster Moonwatch Professional has been unveiled gives another view of this luxurious model. Indeed, this Moonwatch 321 Platinum was actually a “teaser” of most of the updates to be found in the regular production steel watches launched in 2021, such as the slightly redesigned case, the comeback of the step dial, the double-step caseback, the teardrop seconds hand, the updated logos and fonts or the historic layout of the bezel.

Omega Speedmaster Moonwatch 321 Platinum 311.

The renaissance of an Icon

Having slumbered for more than five decades since production ended in 1968 (at least, for Omega), the news that Omega would be awakening the calibre 321 was music to the ears of Speedmaster fans. A special division of Omega’s manufacture was set aside to breathe life into the calibre. Operating in top secrecy for two years with the code name “Alaska 11”, the mission was to reconstruct the movement as accurately as possible. Using digital scans to probe a Speedmaster ST 105.003 worn by Gene Cernan on the Apollo 17 mission of 1972, all the parts of the calibre 321 were reproduced to scale. This high regard for the original meant that Omega’s Co-Axial technology and Master Chronometer certification were out of the question.

Omega Speedmaster Moonwatch 321 Platinum 311.

Viewed from the caseback, admirers of the original 321 will notice how the bridges, levers, gears and plates look identical to the original although the finishings and engravings are sharper and more detailed. The bridges and mainplate, for example, are plated with Senda gold and the bevels are polished. Another heart-warming fact is that the entire assembly of the movement, including the watch head and bracelet, is executed by one watchmaker. Even though the movement still beats at the original slow pace of 18,000vph, the power reserve has been extended to 55 hours.

Omega Speedmaster Moonwatch 321 Platinum 311.


The word that keeps coming to mind when I think about this watch is “majestic.” There is something regal, almost aloof about this heavy platinum watch with its cold stone dial and fragments of lunar meteorite. However, the dial’s cold majesty is compensated by the view on the caseback inviting you to dive into the fascinating animation provided by calibre 321 with its warm18k Sedna gold bridges and mainplate. On the other hand, it might go a bit too far in terms of luxury, compared to the original spirit of the Speedmaster, which was an instrument watch after all. Its scarcity is destined to make this watch a collector’s item.

Availability & price

The Omega Speedmaster Moonwatch 321 Platinum comes on a black alligator strap with a platinum pin buckle and retails for EUR 59,200. It isn’t limited in number, but production is limited by the availability of the calibre 321 (and most of them will equip the steel 321 Moonwatch).

For more information, please visit Omega Watches.

3 responses

  1. I can sort of see why someone might want the original version of the watch this is copying, but to pay all of that and not get the benefit of the the co-axial escapement seems odd because it is a new watch.


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