Everything You've Ever Wanted To Know About The Patek Philippe Two-Crown World-Time Ref. 2523 Wristwatch

Everything You've Ever Wanted To Know About The Patek Philippe Two-Crown World-Time Ref. 2523 Wristwatch

Phillips Watches Specialist Marcello de Marco goes deep on one of the most important Patek Philippe wristwatches to come to auction this season.

Phillips Watches Specialist Marcello de Marco goes deep on one of the most important Patek Philippe wristwatches to come to auction this season.

Our first live auction of 2024, the PHILLIPS Geneva Watch Auction: XIX, takes place on May 11 and 12, at the Hotel President, at Quai Wilson 47 in central Geneva. The auction includes more than 215 of the world's finest watches – and though we are loath to boast, we truly think it's one of the best catalogs we've ever put together. We'll be highlighting a number of the most interesting lots and stories featured in the sale over the next month, including the Patek Philippe Two-Crown World-Time ref. 2523 featured in this article.


– By Marcello de Marco

There are watch models that in virtue of their historical importance, rarity and attractiveness have soared above all the rest and are regarded unanimously by the community as “watch collecting endgame”: pieces that, once acquired, a connoisseur can feel to have reached the utmost top of collecting, he or she becoming part of an ultra-exclusive club which only the most discerning and demanding collectors can say to have joined. The two-crown Patek Philippe worldtime is potentially the very first model to reach this kind of “ultimate grail” status, achieving it as soon as 1989, when an example was chosen as cover lot of the “Art of Patek Philippe” auction. Since then, its popularity has been steadily increasing - a trend which seems nowhere close to ending.

The example included in our upcoming Geneva Watch Auction: XIX is without a doubt one of the most appealing and collectible Patek Philippe two-crown worldtime wristwatches to ever come to market in virtue of its unpolished case which perfectly preserves all the details of its peculiar architecture in absolutely unmolested condition. All the facets of the lugs are perfectly preserved, with sharp edges. The inward step where the lug joins the band is incredibly prominent, the satin finish is original and unspoiled and the hallmark is a joy to behold.

Lot 55: A circa 1960 Patek Philippe Two-Crown World-Time ref. 2523 wristwatch in 18k yellow gold. Estimate: CHF 1,200,000 - 2,400,000

The dial is as impressive as the case, featuring a city ring with strong engraved/enamelled graphics in beautiful contrast with the metallic finish. The guilloché center is absolutely pristine, without hints of oxidation. The 24-hour ring features perfectly preserved graphics, without signs of fading. Such remarkable condition is not only a rarity but also a necessity if one is to admire this design in all of its unabashed beauty, especially concerning the case: even the most minute rounding of the edges dramatically alters its aesthetic effect which so strongly relies on facets and edges to convey its power.

The World Time System

The complication is defined by the presence of two rings: a fixed - but adjustable - one with the 24 time zones, and a second 24-hour ring, usually divided in nocturnal and diurnal halves for easier readability, revolving counterclockwise. This simple but brilliant system allows for the correct time for each city to be read on the respective adjacent segment of the 24-hour ring: a true Columbus’ Egg of watchmaking.

The worldtime complication is a direct consequence of the advancements in the field of communication technology. While today it is rightfully identified as a traveler’s complication, its original purpose was in fact more “static”; the earliest examples do not even have a system to adjust the time zone. In its first conceptualisation, it meant to allow people with international business/interests to track simultaneously the time everywhere in the world. Imagine being PanAm CEO in the 1950s, and having to place consecutive calls (a real-world situation, since the mid first half of the past century) to your Tokyo, Rome, New York and Sydney offices. Knowing what time it is in each city helps you plan the calls. That is why watchmaker Louis Cottier developed the system in the 1930s, when intercontinental telecommunication was beginning to be more commonplace. Very early in it’s evolution, however, the revolving city ring was introduced, thus “consecrating” forever the worldtime as a traveler’s timepiece.

Lot 55: A circa 1960 Patek Philippe Two-Crown World-Time ref. 2523 wristwatch in 18k yellow gold. Estimate: CHF 1,200,000 - 2,400,000

Reference 2523 is in fact the final step (in vintage wristwatches) of a refinement process that had begun two decades earlier. The very first Patek Philippe examples of the system involved a fixed city ring (as mentioned, without the possibility of easily changing the local time zone) and were executed as practically one-off -pieces such as reference 515 (a rectangular model), two modified examples of reference 96 (96HU), and references 542 and 1416, two 3-piece series, probably market tests - together with a prototype series of three 1415 examples.

The first serially produced model was reference 1415, featuring a 31mm diameter and a rotating 24h ring and fixed city bezel, allowing for user-friendly change of time zone. In fact it proved itself quite successful - for such a new and unorthodox model - with about 115 pieces made mostly during the 1940s.

The evolution of ref. 1415, reference 2523 is miles away from its ancestor in terms of design. It features an oversize-for-the-time 36mm case, two crowns (one to set the city ring) and a city ring which becomes integral part of the dial rather than being engraved to the bezel (a “bead and notches” system allows for the city ring to smoothly snap into place at each time zone, a detail which highlights the attention Patek Philippe reserved to this model).

Lot 55: A circa 1960 Patek Philippe Two-Crown World-Time ref. 2523 wristwatch in 18k yellow gold. Estimate: CHF 1,200,000 - 2,400,000

It would seem that such elaborate and refined aesthetics - which make the timepiece so iconic and attractive nowadays - were
too ahead of their time: reference 2523 was in fact a commercial disaster, and consequently production was very limited. A slightly modified version (ref. 2523-1, the present watch) was launched as well, but with no different outcome.

The importance of this model is well recognised by the brand itself: 3 examples are housed in the Patek Philippe Museum.

Combining rarity, technical proficiency, mind-blowing good looks and ultimate exclusivity, this watch is unarguably one of the most important timepieces in existence and it would be the crown jewel of even the most important wristwatch collection.

Louis Cottier

Born in Geneva in 1894 to automata-maker Emmanuel Cottier, Louis Cottier was consequently in contact with watch/automata- making since the very beginning of his life. He was formally trained in watchmaking at the École d’Horlogerie in Rue Necker, Genève. During these years, he was classmate with Edouard Wenger - celebrated casemaker and lifelong friend - and trained under watchmaker Henri Hess, whom he held in the highest of regards. He will later recall “In 1908, we (Edouard and I) were side by side in the class of Herni Hess ... none (other teacher) has left such a deep and lasting mark as Henri Hess did.”

After school, he worked for Jaeger until 1931, when the Great Depression had him loose his job and subsequently set up his
own shop in Geneva at 45, Rue Vautier. It is with the introduction of the worldtime system that same year (patent no. 270085) that he made his name immortal. In fact, the inspiration for the idea came from his father’s unsuccessful attempt at tackling the same problem. When introduced, the worldtime complication was a truly novel complication, with a completely new aesthetic layout and which address a previously non-existent need. The novelty effect was in fact a success, and companies such as Vacheron Constantin, Agassiz (today known as Longines), and Rolex were also among Cottier’s clients.

Louis Cottier. Image credit, Jean-Pierre Cottier.

In 1947, he moved to 20, Rue Ancienne and began to industrialise and improve his production methodology. It is during these years that he acquired the trust of Rolex’s founder Hans Wilsdorf to the point that, also thanks to the recommendation of horological historian Alfred Chapuis, he was appointed curator of his collection, a post most congenial to him also due to his love for history. He was in fact also a dedicated scholar of Genevan History, and his renown in the field was so high that important collectors would go to him asking not only for restorations, but also for historical researches on their timepieces. Furthermore, he was also a talented painter and aquarellist.

He kept on developing new horological solutions, mostly for Patek Philippe, such as the present two-crown update to his worldtime system (1950); a 1954 wristwatch with double dial but single movement (a world’s first) and 1958 linear hour watch (which is the inspiration for the contemporary Urwerk’s “Cobra” timepieces). His final contribution to watchmaking history comes in 1959, when he patented the jump-hour travel time system found on Patek Philippe reference 2597. He passed away on September 16, 1966 in Carouge, the Geneva neighbourhood where he lived and worked for virtually his entire life.

Technical Analysis

Movement: The overall execution of the timepiece is, from a purely technical standpoint, absolutely extraordinary. The watch
is powered by one of Patek Philippe’s most reliable “time only” movements of the time, 12 lignes calibre 12’’’400, personally modified by Louis Cottier - the inventor of the world time system. The legendary watchmaker in fact insisted for personally executing the final assembly of every single piece (and to hand-make the hands) of the production.

Lot 55: A circa 1960 Patek Philippe Two-Crown World-Time ref. 2523 wristwatch in 18k yellow gold. Estimate: CHF 1,200,000 - 2,400,000

Dial: Going beyond the usual Patek Philippe quality, the restricted production output and the differently decorated dials meant that each one of these watches was treated practically as a Pièce Unique - the most important components practically as a Pièce Unique - the most important components of the movement and dial hand-finished and univocally linked to each watch: in fact, a movement number can be found on virtually all the main parts, including the 24 hour disc (last three digits stamped to the back), the city ring bracing (last three digits hand-engraved to the front), obviously on the movement (both sides), and also to the underside of the guilloché disc together with Louis Cottier’s monogram LC. This last detail is not only an intellectual “Easter Egg”, but it underscores the fact that the legendary watchmaker insisted for personally executing the final assembly of every single one of these specimens (and to hand-make the hands).

Case: Made by Geneva-based Antoine Gerlach - poinçon number 4 in a Key - it is one of the most fascinating and complex Patek Philippe designs. Already, the inclusion of a second crown - making this the only vintage single-dial Patek Philippe model sporting 2 crowns - was extremely avant-garde. The large 36mm diameter was also destined to raise eyebrows, especially when found in an elegant gold Patek Philippe dress watch. However, it is the design of the lugs that will live on as one of the most brave - and ultimately impressive, even though it took decades to be appreciated - architectures employed by the brand. These cases in fact present a distinct evolution:

- The lugs of ref 2523 are consistent throughout production, faceted and raised above the bezel. The case numbers for ref. 2523 are randomly found within the 306’1xx/306’2xx range, with one outliers (305’699).
- The cases of ref. 2523/1 feature instead consecutive numbers and present an evolution
- Earlier watches (First Series - lowest case no. known: 313’036; Highest: 313’043) feature a more streamlined, facet-less lug design. The lugs are not raised above the bezel.
- Later pieces (Second Series - lowest known case: 724’044; highest: 724’051) reintroduce the faceted design of ref. 2523
but keep a lower height, with the lugs not going above the bezel. Practically, this last evolution strikes the sweet spot between the previous two.

Lot 55: A circa 1960 Patek Philippe Two-Crown World-Time ref. 2523 wristwatch in 18k yellow gold. Estimate: CHF 1,200,000 - 2,400,000

A downside of the faceted lugs design is that the soft gold edges are very sensitive to polishing, with many examples of the model featuring rounded edges. Luckily, the present instance happens to be one of the very few case which survived absolutely unpolished until today, allowing us to admire this architecture in all of its glory. Possibly to to its original lukewarm reception, Patek Philippe employed a remarkable range of dials for this reference maybe as an effort to lure in clients with different tastes. The model is known with plain silvered dial (2523-1 First Series), blue enamel dial (found on 2523), cloisonné enamel dials (2523) and engine-turned dial (found both on 2523 and on Second Series 2523-1, albeit different designs). The city ring as well features an evolution, with earlier version featuring a matte grené finish while the Second Series of ref. 2523/1 - the present watch - features a metallic-finish dial very much in tone with the guilloché center for a somewhat futuristic/ steampunk effect.

A recap of the dial evolution for the model looks as follows:

Ref. 2523 can feature (without real chronological order) the following dials (and the city ring is matte):
- golden guilloché dial
- blue enamel dial
- cloisonné dials

Ref. 2523-1 can feature:
- First Series: plain silvered dial, matte city ring - earliest known: 724’302, latest known: 724’309.
- Second Series: silvered guilloché dial, metallic city ring - earliest known: 724’310, latest known: 724’310.

Production Details And Numbers

A comprehensive list of all the known 2523/2523-1 is summarised in the table below, which shows us that: The production of reference 2523 movements was made in two batches, one starting with movement no. 720’300, and the other with no. 722’700. Yellow, pink and white gold examples are known. The latest known movement no. of the first batch is 720’308, and movement 720’312 is a ref. 96, thus the total output of this batch is between nine and 12 pieces.

Lot 55: A circa 1960 Patek Philippe Two-Crown World-Time ref. 2523 wristwatch in 18k yellow gold. Estimate: CHF 1,200,000 - 2,400,000

The latest known movement no. of the second batch is 722’719, and movement 722’724 is a ref. 2431, thus the total output of
this batch is between 20 and 24 pieces. Consequently, the total output for reference 2523 must be between 29 and 36 pieces. The production of reference 2523-1 is even more restricted, most likely around 20 pieces in total with consecutive movement numbers and a production evenly split between First and Second Series.

First Series (flat lugs, plain silvered dial, matte city ring): most likely starting with 724’300 (but the earliest known is 724’302) up to 724’309 - potentially 10 pieces, 5 are known all in yellow gold. Second Series (faceted lugs, guilloché dial, metallic city ring - the present watch): they start at 724’310 and the last known example is 724’318 - most likely it was made in around the same numbers as the First Series but no movement number has appeared on the market from 724’319 to 724’334 (a ref. 2500R). Eight Second Series pieces are known, four in yellow gold and four in pink gold.

Below, a list of all known watches:

2523: FIRST BATCH

720’300 - 305’699 - YG - Guilloché 720’301 - 306’193 - YG - Eurasia 720’302 - unknown
720’303 - 306’197 - YG - Eurasia 720’304 - 306’201 - YG - Eurasia 720’305 - unknown

720’306 - unknown
720’307 - unknown
720’308 - 306’199 - YG - Gold Guilloché 720’309 - unknown
720’310 - unknown
720’311 - unknown
720’312 - ref. 96

2523: SECOND BATCH

722’700 - 306’202 - YG - Guilloché 722’701 - unconfirmed - YG - Guilloché 722’702 - 306’207 - YG - Guilloché 722’703 - 306’208 - YG - Blue enamel 722’704 - 306’209 - YG - Blue enamel 722’705 - 306’204 - YG - Blue enamel 722’706 - 306’205 - YG - North America 722’707 - 307’475 - WG - North America 722’708 - 306’210 - YG - North America 722’709 - 306’211 - YG - North America 722’710 - 306’206 - YG - South America 722’711 - 306’212 - YG - South America 722’712 - 306’213 - PG - Guilloché 722’713 - unknown

722’714 - 306’215 - PG - Blue enamel 722’715 - 306’216 - PG - Blue enamel 722’716 - 306’217 - PG - North America 722’717 - 306’218 - PG - North America 722’718 - unknown

722’719 - 306’220 - PG - South America

2523-1 First Series

724’300 - unknown 724’301 - unknown 724’302 - YG - silvered 724’303 - YG - silvered 724’304 - YG - silvered 724’305 - unknown 724’306 - unknown 724’307 - YG - silvered 724’308 - Unknown 724’309 - YG - silvered

2523-1 Second Series

724’310 - YG - guilloché 724’311 - YG - guilloché 724’312 - YG - guilloché 724’313 - unknown 724’314 - YG - guilloché 724’315 - PG - guilloché 724’316 - PG - guilloché 724’317 - PG - guilloché 724’318 - PG - guilloché

Combining rarity, technical proficiency, mind-blowing good looks and ultimate exclusivity, this watch is unarguably one of the most important timepieces in existence and it would be the crown jewel of even the most important wristwatch collection.

You can learn more, place a bid, and view the entire Geneva Watch Auction: XIX catalog here.


About Phillips In Association With Bacs & Russo

The team of specialists at PHILLIPS Watches is dedicated to an uncompromised approach to quality, transparency, and client service. Phillips in Association with Bacs & Russo holds the world record for the most successful watch auction, with its Geneva Watch Auction: XIV having realized $74.5 million in 2021. Over the course of 2021 and 2022, the company sold 100% of the watches offered, a first in the industry, resulting in the highest annual total in history across all the auction houses at $227 million.

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