The very first reference in the revered line of Rolex Daytona chronographs is the present model, reference 6239. Launched in 1963 in the USA, and the following year in Europe, this reference is the beginning of what is arguably the most recognized line of chronographs ever produced. Adding to its already remarkable appeal, the present specimen furthermore comes with a wonderfully tropicalized dial: the three subsidiary counters shifted toward an absolutely even chocolate hue. Such discoloration is the result of atmospheric agents (UV light, humidity, oxygen) reacting with the black paint. Not only this effect occurs just on a minority of watches, but it is furthermore highly unpredictable: only a small fraction of tropical dials achieves such a perfectly even and warm tone as the one of the present watch.
The present piece, with a case number around 1.5 million, is a very early example, as it was manufactured just 4 years after the introduction of the model. Indeed, the bezel is correctly a Mark II, characterized by the hash mark for 275 UPH.
This reference was fitted with three different calibres: early examples (1963-1965) have cal. 72B, then from ’65 to ’67 circa cal. 722 was used, and from ’67 on cal. 722-1, such as the one found on this piece.
Interestingly, Mark II bezels were discontinued around the same time cal. 722-1 started to be used. It is a reasonable assumption that only an extremely small number of 6239 was born with a Mark II bezel and 722-1 calibre.