A seminal world timer updated for 2019, the Patek Philippe World Time Ref. 5231J is a horological work of art that is nearly impossible to get.The Patek Philippe World Time Ref. 5231J is new for 2019, sitting alongside the existing 5231 that comes in a platinum case with that matching platinum beads-of-rice bracelet that defines peak low-key decadence. Housed in a 38.5mm-wide and 10.23mm-tall yellow gold case, the 5231J is slightly smaller than the 39.5mm wide 5231. This is the same case youll find on the 5230 world timers, which are a little more accessible, due to the fact that they have the less elaborate guilloche center dial rather than the enamel. The smaller 38.5mm-wide case is preferable, though, as it doesnt have the Patek Philippe text engraved on the bezel at 12 oclock and Geneve at 6 oclock. I just think contemporary tastes dont lean toward bezel engravings (or elaborately stylized fonts, for that matter). Several people have rightfully pointed out how the 5231J is reminiscent of the highly rare Ref. 2523 (which sell in auction for well into the millions of dollars), introduced in the mid-1950s and, perhaps, the grail Patek Philippe world time watch. Notably, the winglet-style lugs and polished flat bezel that youll see on this case were introduced with the 5230 world timer in 2016. This was a big year for changes to the world time watch due to global governmental changes like Moscow shifting from UTC+4 to UTC+3 and global power shifts resulting in new cities for a time zone (Dubai replacing Riyadh would be one).The Enamel DialThe 5231J is characterized by the cloisonne enamel planisphere at the center of the dial. Cloisonne is one of four enameling techniques Patek uses. The process involves taking a thin gold wire and bending it to the shape of an intended design. The wire is then fixed to the baseplate, which has an enamel layer coating. After the cells formed by the wire are filled with enamel, the process then involves several firings, depending on the specific color and effect theyre trying to achieve.The enamel center depicts Europe, Africa, and the Americas in a series of greens, brown and yellow, and blue for water. Its absolutely a work of art when you observe it close-up in person. From the center of the enamel dial are the (quite short) 18k yellow gold ring-shaped hour hand and dauphine minute hand. As you could guess, legibility is hampered by having short, polished yellow gold hands over such a rich enamel backdrop. Id say its an unfortunate side effect inherent to the nature of this watch, but I wouldnt argue with anyone who thinks that the ring-shaped hour hand is an unforced error. The World Time FunctionAlong the outer ring are the names of 24 cities, each representative of a time zone. At 10 oclock, youll see the pusher that, when engaged, moves the time forward one hour (the minute hand is unaffected), as well as the city ring and 24-hour ring. The red arrow at 12 oclock will be pointing toward the city that corresponds to the time zone youre in. Sure, you cant get quite the precision of a second-time zone indicator that can allow 30 or 45-minute increments (there are a total of 37 time zones, globally, when you consider these), but the ease and elegance of operation here is world-class.And lets not fool ourselves: A Patek Philippe World Time Watch is one of those things that only Logan Roy from Succession wouldnt be floored by - though maybe he would have been more impressed with, It tells you how rich you are in 24 time zones, rather than boot-licking future son-in-law Tom Wambsgans amazingly cringe-worthy line, Its incredibly accurate at telling you how rich you are, when gifting a Patek.The 5231J uses the Caliber 240 HU (thats Heure Universelle for all you Globeheads out there), which, of 239 parts, including the 22k gold rotor, the 240 HU has a power reserve of 48 hours. Whats really of note about the 240 HU is that it is remarkably thin at just 3.88mm-thick, which is made possible through a patented design that allows for the winding rotor to be integrated with the bridges. In comparison, the Vacheron Constantin Caliber 2460 WT (found in a few pieces, including the Overseas World Time 7700V) is 7.55mm-thick and the Jaeger-LeCoultre Calibre 772 (found in the Geophysic Universal Time) is 7.13mm-thick. As for the Omega Seamaster Aqua Terra world timer, I am not quite certain about the movements thickness, but I do know the case measures 15.5mm- thick.Few And Far BetweenThe World Time Ref. 5131J is one of Patek Philippes application pieces, meaning that on top of being few and far between, Patek takes extra steps to make sure not many of them end up in the secondary market. So, where the guilloche dial world time watches are pretty available for around their ~40k list price, these enamel world time watches are hard to come by and reach well into the six figures. However, if you are a Patek Philippe customer buying a new 5131J, it will have a price of $73,710. You can learn more at patek.com. [...]