The name El Primero does not simply refer to a watch model, but also to its movement. Launched in 1969, the El Primero caliber was simply revolutionary. It was one of the very first automatic chronograph movements, furthermore designed as a whole rather than being an automatic movement with an added chronograph module. In addition, it vibrated at 36’000 VPH, an astoundingly high frequency for a mechanical watch which ensured superior timekeeping performance. So highly regarded were these El Primero movements that they would later be selected by Rolex as the base on which to develop the movement of the first automatic Daytona chronograph (reference 16520).

The present specimen is one of the earliest incarnations of this movement, dating to the 1970s. The case construction fully reflects the taste of the time, oriented on highly sculpted and angular designs. Such a construction can in this instance be fully appreciated thanks to the unpolished condition of this piece, allowing the beholder to admire every edge and facet in its original glory. The dial, however, is no less enthralling: the once-black outer track and subsidiary dials have evenly aged to an astoundingly charming cappuccino hue. Such a strong tropicalization not only highly enhances the aesthetic virtues of the piece, but it is furthermore an extremely rare occurrence and enormously enhances the appeal and collectability of this remarkable wristwatch.