Two ideas of a watch

Rolex builds sealed sports watches in series; Patek Philippe builds dress watches and complications in small numbers. 98 per cent of the Rolex watches here are rated to 100 m or more, because the Oyster case is the whole brand; 8 per cent of Pateks are, and the median Patek is rated to 30 m. Every Rolex here is automatic; 35 per cent of Pateks are hand-wound and 6 per cent quartz. One per cent of Rolex watches have a display back, 69 per cent of Pateks.

The movements tell the same story. Rolex powers 3,659 watches with 42 calibers, five of which account for 78 per cent; Patek powers 918 with 96, and its five most common, led by the ultra-thin 240 and the 324 S C, cover 35 per cent. The 240 piece explains the micro-rotor that lets a Patek stay under 8 mm; the 3135-to-3235 piece explains the Rolex approach of one movement improved across decades.

Complications

This is where Patek's catalogue lives. 19 per cent of its watches here carry a perpetual calendar, 19 per cent a chronograph, 11 per cent a minute repeater, 8 per cent an annual calendar and 5 per cent a tourbillon, most of them in the Grand Complications and Complications collections, the two largest Patek groups in the library. Rolex's complications are three: the date and day of the Day-Date, the second time zone of the GMT-Master, and the annual calendar of the Sky-Dweller, the only Rolex that knows the month.

Materials and rarity

Both are gold brands in this library, in different ways. 89 per cent of Pateks are precious metal and 9 per cent steel, the steel being the Nautilus, the Aquanaut and a few Calatravas. Half of the Rolex watches are precious metal, 36 per cent are Rolesor, steel with a gold bezel, and 8 per cent are plain steel.

26 per cent of the Pateks here are limited editions and 30 per cent of the scored ones carry a rarity score of 8 or more, the Rare Handcrafts Calatravas among them. Rolex makes no limited editions, and 14 per cent of its scored watches reach 8, mostly gem-set Day-Dates and Pearlmasters.

Where they come closest

The Nautilus at 40 mm and the Datejust 41 are both steel watches with a date on an integrated or Oyster bracelet, and the two chronographs, the Daytona on the 4130 and Patek's 5170 on the CH 29-535 PS, are the one place the brands answer the same brief. The Day-Date in gold and the Calatrava are the dress watches, one an Oyster and one not.