The Oysterquartz traces its roots all the way back to 1970 and the very first quartz watch produced by Rolex, the Ref 5100.  This watch was the fruit of Rolex's participation (along with twenty other Swiss brands) in the Centre Electronique Horloger, which was founded in 1962 by several leading Swiss watchmakers to develop an electronic movement for use in wristwatches.  The final result was the Beta 21, a 13 jewel, 8Khz quartz module first seen in prototype form in 1967.

In 1968 an industrial consortium of Swiss watch manufacturers was created to mass produce the Beta 21.  This was a true collaborative effort among otherwise competing watch companies, all of whom would be using the Beta 21 in their own branded quartz watches.  The CEH itself designed the module and produced the integrated circuit.  Ebauches SA (the forerunner of today's ETA) manufactured the mechanical parts of the movement as well as the quartz oscillator.  Omega was responsible for producing the micromotor that powered the watch hands. This "motor" was really a vibrating unit that drove a tiny horizontal pendulum set to oscillate at 256Hz and this pendulum drove the hands by means of a ratchet and index wheel. (This drive mechanism was virtually identical to that used on the original Bulova Acutron.)  The end result was that unlike with modern quartz movements, the second hand of a Beta 21 watch moved around the dial smoothly—even more smoothly than the highest "hi-beat" mechanical watch of the time.

Final assembly of Beta 21 movements took place in three different manufacturing facilities, with very limited modifications to the movements being made depending on a brand's specifications.  Sixteen different Swiss watch companies began selling Beta 21 quartz watches under their individual brand names in 1970, including Rolex with the Quartz Date 5100.

The 5100 debuted on June 5, 1970 and initial orders far exceeded Rolex's expectation, with the planned limited run of 1000 watches selling out before production even began.  In the end, all 1000 serially numbered 5100s were sold between 1970 and 1972. Today a 5100 complete with box and papers is a highly prized collector's piece.

From an esthetic standpoint the 5100 was a styling triumph, with a clean, modern design that utilized an integrated case and bracelet crafted entirely from 18K gold (about 25% were made in white gold). The crystal on the 5100 was synthetic sapphire, a first for Rolex.  Clearly this was a very unique watch for Rolex, and they focused heavily on its exclusivity and limited production in their promotional materials:

At our Geneva Headquarters, there is a Golden Register, a Who's Who of our clients who proudly count a Rolex Quartz among their most precious possessions. They form the Rolex Quartz Club, one of the most exclusive clubs imaginable because so few of these revolutionary timepieces are being made. Members of the Club are always welcome at Geneva. On their first visit, they are invited to sign the Golden Register and can enjoy a personal tour of the Geneva world Headquarters.

Despite Rolex's own high praise for the 5100, this watch was an anomaly for the company.  Because they had to work with an existing movement, and only limited modifications could be made to it, Rolex essentially had to design the Quartz Date around the the Beta 21 module.  This meant that the Oyster case (upon which Rolex had built their reputation for the past forty years) could not be used and the 5100 was listed as "water resistant" rather than "waterproof."  In addition, the 5100—despite having the Rolex name on the dial—contained a movement that for all intents and purposes was identical to that found in the watches of sixteen other companies. This put Rolex in a rather untenable position, one they had not been in since the early days when J. A. Aegler produced movements for both Rolex and Gruen.  For these reasons, one can surmise that Rolex was never completely happy with the 5100 despite the overwhelmingly positive response it received from the watch buying public.  Consequently, in 1972 they withdrew from the CEH as well as the Beta 21 consortium and began developing a quartz movement of their own design and the watch that would house it, the Oysterquartz.



The Smithsonian Institution
Prometheus Bound by Carlos Perez
The Omega Marine Chronometer Page
The Rolex Report by John E. Brozek

Photo Credits:

5100 with map background: James Dowling
Other photos: Unknown


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