Manufacturer: Rolex Year: 1963 Reference No: 6239 inside case back stamped 6238 Case No: 923'349 Model Name: "Double Swiss Underline" Cosmograph Material: Stainless steel Calibre: Manual, cal. 72B, 17 jewels Bracelet/Strap: Stainless steel Rolex Oyster bracelet, reference 7205, end links stamped 57, max length 175mm. Clasp/Buckle: Stainless steel Rolex folding deployant clasp stamped 4.69 Dimensions: 36.5mm. Diameter Signed: Case, dial, movement and bracelet signed Literature: Another example of a reference 6239 "Double Swiss Underline" with black dial is illustrated in Ultimate Rolex Daytona by Pucci Papaleo, pages 104 and 105.
Catalogue Essay
The year 1963 was, without a doubt, a breakthrough period for Rolex. It was most notably the first year that reference 6239 was introduced. Named the "Cosmograph" wristwatch, the tachymeter scale was for the first time moved from the dial, to the bezel. Most interestingly, the model was originally marketed as the "Le Mans". Yet, it was eventually dubbed the "Daytona” when Rolex sponsored the 24 Hours of Daytona automobile race.
The present watch is among the very first examples of reference 6239 ever produced, and displays all the correct attributes of the exceedingly popular "Double Swiss Underline". The bezel, firstly, is the most earliest variant produced by Rolex. A Mk 1 example, it is calibrated to 300 units per hour, and features small hash marks. Later examples would feature dots instead of hash marks. It is also recognizable by the 275 intermediary unit, which cannot be found on later examples.
The black dial is the most compelling aspect of the watch, namely in its "Double Swiss" designation. Rolex had originally used stamps that were designed for use on previous models. Since the bezel of the new "Cosmograph" was larger, and covered the edge of the dial, Rolex had to redesign the stamps, and print "Swiss" again, this time immediately visible to the viewer. Today, this "Double Swiss" designation is very collectible, providing scholarship for the collector.
Most striking is the "underline" below the Rolex Cosmograph signature, which can be seen on a range of Rolex watches manufactured around 1962 to 1964, ranging from the GMT-Master to the Submariner. Many in the Rolex community believe the "underline" was used it was to signify a transition from radium to tritium on the dial.
Other small details pull the watch together, such as the 6238 case back, which is correct as Rolex usually used the leftover case backs from previous models. The hands are also slightly longer and thinner, almost touching the edge of the hour markers.
A historically interesting and aesthetically wonderful watch, the present example delights not only in its rarity, but also in its condition and overwhelmingly correct attributes.
Founded in 1905 England by Hans Wilsdorf and Alfred Davis as Wilsdorf & Davis, it soon became known as the Rolex Watch Company in 1915, moving its headquarters to Geneva in 1919. Like no other company, the success of the wristwatch can be attributed to many of Rolex's innovations that made them one of the most respected and well-known of all luxury brands. These innovations include their famous "Oyster" case — the world's first water resistant and dustproof watch case, invented in 1926 — and their "Perpetual" — the first reliable self-winding movement for wristwatches launched in 1933. They would form the foundation for Rolex's Datejust and Day-Date, respectively introduced in 1945 and 1956, but also importantly for their sports watches, such as the Explorer, Submariner and GMT-Master launched in the mid-1950s.
One of its most famous models is the Cosmograph Daytona. Launched in 1963, these chronographs are without any doubt amongst the most iconic and coveted of all collectible wristwatches. Other key collectible models include their most complicated vintage watches, including references 8171 and 6062 with triple calendar and moon phase, "Jean Claude Killy" triple date chronograph models and the Submariner, including early "big-crown" models and military-issued variants.