Certifications in horology

Written by:Andrea Casalegno|

An inaccurate watch is like a car without the engine. From the need to be reliable, as old as the first timepiece, comes an even more emblematic and articulated one: to certify this same precision.

Over the years, research has led to ever higher accuracy standards, which go to deepening different aspects, from movement alone to the complete production chain. Today, scrolling through a catalogue or talking with enthusiasts, it is easy to hear about certifications, some more classic and historical, others newer and more in-depth.

To make our way through these certificates, we decided to explain to you how they are born and what are the most common ones.


Let’s start with the most famous certification: the Chronometric Certificate from the Contrôle Officiel Suisse des Chronomètres

This institution, known to most as COSC, has been responsible since 1973 for issuing a timekeeping certificate to movements that pass a certain set of checks.

For the uninitiated, the name of Chronometer is in itself synonymous with precision in watchmaking. Only watches that are recognized as such by institutions like the one mentioned above can use this attribute.

Originally chronometers were mainly dedicated to the navy and observatories, where higher reliability was required. To date, certification is much less dominant than in the past, but it still is a source of pride.

In Geneva, Bienne and Le Locle Contrôle‘s facilities , only movements sent by the various manufacturers are tested. The institute requires calibers to be equipped with a continuous second hand and a white dial with seconds indexes, in order to check whether the daily difference is between -3 and +6 seconds per day. In addition to the certificate you can also request the march bulletin of the 15 days of testing at various temperatures, which shows the trend of accuracy and deviations over time.

Among maisons that require services from COSC every year, Rolex, Omega and Breitling stand out, with 800, 400 and 150 thousand certified movements respectively.

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The Vipère

In 1897, the Besançon Observatory decided to stamp a viper’s head on the movements it certified as appropriate for its business. Since then, the Tête de Vipère has become a symbol of pride in history, becoming the only French institution to issue this type of certificate.

After years of oblivion, it has recently been rediscovered and adopted by brands such as Tag Heuer and Kari Voutilainen. It represents a more detailed certification than the COSC, but very similar in terms of parameters.

The Geneva Seal

Probably the oldest certification in history, it symbolizes the excellence of Helvetic watchmaking. Born in Geneva at the end of the 1800s, “promoted” only 5 maisons in 130 years of history. We are talking about Patek Philippe, Cartier, Vacheron Constantin, Chopard and Roger Dubuis.

Unlike COSC certification, the Seal considers the watch as a whole, subjecting it to the judgment of tests and a committee. Originally managed by the Geneva’s ” École d’Horlogerie”, is now entrusted to Timelab, an independent laboratory, which is responsible for keeping alive the tradition of the Seal.

During the evaluation, every detail is taken into account before placing the “coat of arms” on the movement: from finishes to cases, from assembly to decorations…
Even carried out tests are no longer the same as before. In addition to the accuracy, the water resistance, the power reserve and of course the origin of the watch is checked.

With its characteristic symbolism, the Seal stands as a certificate of the most sublime Swiss watchmaking, safeguarding the attention to finishes and overall quality.

Self-certifications: Patek Philippe’s Seal

When accurate tests and juries are too much, it’s best to do things your own way.

Patek Philippe fully embodies this policy, from the boutiques directly owned by the brand, to the entire production chain. The Genevan house understood that “homemade” is better.

In 2009 Thierry Stern’s brand abandoned the Geneva Seal and established its own, which provides a quality guarantee on all components of the watch. If it sounds like a repetition, it is good to point out that we are no longer talking about movements, cases and dials, but also about straps, hands and pushers, etc.

Although in the eyes of many it may seem that the brand is “signing itself its check”, the seal seems not to have aroused great suspicion.

Behind this move there is not a fear of failing the tests or not being up to the Seal. The truth is the will to put itself on another level compared to all the others. A level so high that it needs its own quality certificate, almost defiantly.

If you are wondering what the public’s reactions are, given the huge row outside Patek’s boutiques, it seems that there is no great doubt.

It is clear, therefore, that certifications are aimed at giving luster and reliability to the eyes of the world, to one of the leading sectors of the Swiss economy.

In these years of rediscovering the watch as a luxury object after the bustle of quartz, it has become important to enshrine the quality and care of Swiss Made compared to the rest of the world, even with measures like these.

Although in 2019 the vast majority of watches on the market are precise enough for our daily life, certifications represent in a certain way a link with the history and evolution of an industry that, day after day, works to create better and more advanced products.

Translated by Lorenzo Spolaor (@lorenzospolaor)

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