The incredible lightness of Zenith's El Primero Lightweight

Two months before Heuer, Breitling and Büren introduced the Calibre 11 in March 1969, Zenith outdid its competitors by running a race against the clock and releasing its El Primero calibre. The movement was genuinely innovative. It shook the foundations of horology with its unusual frequency of 36,000 vibrations per hour, because the standard frequency at the time was 28,800 vibrations. It was also the first wristwatch to be equipped with a self-winding mechanism and a chronograph.

Zenith watches in the race for the ultra-light

Georges Favre-Jacot founded the brand with the star logo in 1865. After being taken over by the LMVH group in 1999, the brand got back into the race.

And Zenith is back in every sense. It has returned to make history – as did Felix Baumgartner when he broke the sound barrier in free fall – and to take back solid watchmaking values. It’s also reemerging to vindicate what makes manufactures worthy of their names: their precious independence.

Among the many values that have always driven watchmakers to dig deeper is the quality of being ultra-light without the timepiece's functioning being affected. This is an area that continues to produce considerable innovation. The El Primero movement – now almost a brand within the brand – offers endless perspectives that represent a substantial asset when it comes to marketing and polishing a brand's image. The number of calibres or eponymous chronographs that seek to reference keeps growing. One of them is the Zenith El Primero Lightweight, a watch that measures a good 45 millimetres in diameter and stems from the Striking 10th collection. This avant-garde timepiece is, as its name suggests, ultra-light. Such a feat was possible thanks both to the high-tech material used to create the outspokenly sportive case and thanks to the titanium and silicon movement.

Avant-garde materials and evolutionary skill for the Zenith El Primero Lightweight

The heaviest components of the movement are usually manufactured in brass. In this movement, the brass has been replaced with titanium for the mainplate and the five bridges, that is, the bridge of the barrel, the balance, the lever, the escapement wheel and the chronograph. The lever and escapement wheel are both made of silicon, and now so is the famous double chronograph wheel. Openwork craftsmen have done the rest to ensure lightness. The self-winding El Primero 4052 W – composed of 334 components and 31 rubies – only weighs 15.45 grams, in contrast to the 21.10 grams for the classic version of the same movement. Lightness was the main mission when creating this movement, but there were other results, such as anti-magnetism, hardness (harder than steel), and a calibre that still delivers maximum efficiency with a 50-hour power reserve. Not to mention the gorgeous oscillating mass with côtes de Genève decoration.

The spirit of competition arises from the carbon fibre, which gives it an attractive black colour and checkerboard pattern. This same material was used to produce the case, which is water-resistant to 50 metres, and the hollowed horns. The surfaces of its internal structures are made of ceramic-coated aluminium. Besides being lighter, this material ensures robustness – 1,800 Vickers, as opposed to 160-200 for 316L steel.

The skeletonisation of the El Primero Lightweight's dial is worthy of praise. Its contours highlight some original aesthetic designs replete with  references that have been adapted to the collection’s codes. The timepieces come in three colours,  pale grey, blue and anthracite, as the same as iconic watches of the original El Primero from 1969. The same disc-date display was used, albeit in a rejuvenated, lightened version. The indexes are rhodinised, faceted and treated with SuperLuminova SLN C1. Under the sapphire crystal, the second hand bearing a small Zenith star displays the famous one-tenth of a second that is produced when time is segmented at 36,000 vibrations per hour. For the record, the number of vibrations is a multiple of the 3,600 seconds that make up the hour.

The brand from Le Locle will celebrate its 150^th anniversary in 2015. Undoubtedly, by then, other variations and versions equipped with the famous El Primero caliber will be around to round off the brand's offer. The Zenith El Primero Lightweight and its timeless Nomex-coated black rubber bracelet with triple-deployment clasp will have nevertheless offered an interesting digression into lightness and illustrating Zenith’s craftsmanship and well-known daring.