Patek Philippe 5131J

Back in 2013, you could have walked into a Patek Philippe boutique and purchased this 5131J for £45,000, but if you wanted to buy one now, you wouldn’t get much change from £100,000. Why is this little world timer now worth double?

The 5131J is part of Patek Philippe’s World Time collection, a complication that offers the time from any one of twenty-four cities at just the press of a button. This is thanks to the calibre 240, an unsurprisingly beautiful micro-rotor movement finished to an equally unsurprisingly high standard. So high, in fact, that the traditional Geneva Seal of excellence wasn’t enough for Patek Philippe, so it went and created its own seal instead.

But we’re not here for the movement, despite the skill and patience required to manufacture one; we’re here for something else that requires even more skill and patience than that, if you can believe it. Take a look at the dial; there are two things to notice about it. The first you probably won’t realise without it being pointed out, but there isn’t actually any mention of the brand or where it was made on the dial anywhere. Instead, they’ve been relegated to the bezel.

This is because of the second thing you should notice: in among the different city names—which look suspiciously like they’ve been printed in the font Apple Chancery—is a spot usually taken up by a nice bit of guilloche. Not here, however, because instead we’ve got a hand-painted enamel map of the world.

Amusingly called ‘email’ in French, enamelling is a decorative technique that’s existed for at least four millennia. It’s made with silica—and coloured with a metal oxide pigment—that’s heated to about 1,000 degrees Celsius to melt it into a glossy, translucent coating. Having been painstakingly applied, the risk of cracks or air bubbles appearing during firing is ever-present. In fact, nearly half of the dials finished in enamel fail in production and are simply thrown away. Enamelling must be done right first time—there’s no going back.

It’s a finish that lasts a lifetime, seriously—find an example in a museum and it can be many centuries old, and will still be as rich and glossy and colourful as when it was first made.

To make matters even more complicated, there are several different methods for applying an enamel finish, the most difficult being cloisonné. Naturally, this is the preferred method for Patek Philippe, and it specifically refers to the division of the dial into multiple sections.

Before the enamelling even begins, the dial maker must hand-bend strips of gold wire into the exact shape of the dial design, here the borders of the landmasses on the map. Every curve, every crevice, is bent into shape, with enormous care taken not to overwork the material and break it.

There are no forms or jigs to help them—it’s all done by eye, and yes, it’s just as tedious as you think it is. With a canvas barely two centimetres wide, accurately representing the major coastlines of the world with strips of metal that require magnification to even see requires superhuman patience and dexterity. And the enamelling hasn’t even started.

With the shaped wire complete, it’s time to break out the paintbrushes. These are as far removed from the broad-tipped brush you’d paint your shed with as can be, with tips a few millimetres—and sometimes just a single hair—across. With the enamel powder mixed with distilled water, the—let’s face it—artist, mixes their colours and gets to work.

With careful application, the partitions are filled in with enamel, particular care taken for transitions in colour, such as the lighter blue seen at the coastlines here, and the browns that separate the equatorial deserts from the greenery either side. With the enamel remaining liquid until it’s fired, gradients in colour are especially tricky. I’m sure you’ll remember from your childhood what happens when you mix too many colours together; if it’s not done right first time, all that remains is a dirty mess.

Painting complete, the dial goes to the furnace to be fired, the water boiling off and the enamel melting to form the solid, glass-like finish. It’s a nervous time, as the person responsible for the dial waits to find out if their hard work has all been for nothing. If it is they start again; it isn’t, the work is flatted and polished, ready to feature in the World Time 5131J.

Watchmaking, especially at the high-end, has always been about the precision and skill of the people who assemble them, but with the 5131J, that engineering excellence is shadowed by its artistic equivalent in the cloisonné technique used to create the dial. Think about it—you could buy some art, hang it on your wall and get to look at it every now and then, or you could get a 5131J and get to look at it whenever you want. That’s why it’s worth £100,000.