While the Cosmograph Daytona is certainly the most well-known Rolex chronograph, the company has a rich history in this department, starting well before 1963. Reference 3525 is one of these pre-Daytona chronograph models. Launched in 1939, its most remarkable feature is the fact that is was already water-resistant: it features a screw back, two-piece case, instead of sporting the snap-on bezel commonly seen on watches of this time. This detail earned it its Italian nickname “Monoblocco”. As expected from an early Rolex piece, the serial and reference numbers are stamped to the outside of the back, rather than being located between the lugs as seen on later watches.

The present example of the reference is without a doubt one of the most attractive and collectible to ever grace an auction room. Preserved in remarkable condition, it impresses with its black multi-scale luminous dial which has never been restored, or even washed. All the details are perfectly preserved, including the luminous numerals. Its nearly 80 years of age left only a subtle off-black patina which gets stronger close to the numerals, as expected due to the interaction with the radioactive material. The case as well impresses with sharp edges and intact proportions, denoting surprisingly little polishing. Even the numerals stamped to the outside of the case back, susceptible to both polishing and daily wear against the wrist, are present and very well defined.

Combining historical interest, enthralling aesthetics and superior condition, the present wristwatch is without a doubt a fascinating and highly collectible piece of Rolex history.