History of Chronometer Certifications

According to this excellent article by Teddy Baldassarre’s Mark Bernardo, there are currently six standards for chronometer watches, some of which are brand specific. I was curious to know more about the topic of chronometer specifications after learning about METAS: the second certification most modern Omega watches go through in addition to that of the COSC. I wondered about the need to make a watch go through two certifications. As it turns out, the point is to ensure that the movement inside the watch won’t fail and will keep very good time, something that was crucial many decades ago for navigators, pilots, and scientists who needed to know the precise time (not so much today). However, now there are even more certifications; let's talk about the two main ones after discussing the brief history of chronometer certifications. 

Source: www.teddybaldassarre.com

Where It All Began: Marine Chronometers 

Long before GPS, navigators and explorers used analogue tools to find their way around the globe. Marine navigators, especially, needed precise timekeeping devices to calculate their routes using a sextant, in other words, to determine their position in relation to celestial bodies. Back then, having a reliable and precise clock was paramount to having a safe journey. The first marine chronometers were developed in the 18th century by British watchmaker John Harrison, who created no less than five versions of the first chronometer marine clock to aid in navigation. His clocks were so precise that they would be accurate within a third of a second per day. (To know more about John Harrison’s career and achievements, I recommend this article on Worn & Wound. If you're really interested, Dava Sobel's Longitude is a great book on the topic) Because the most precise clocks were engineered for maritime navigation, there lies the explanation behind the name of “marine chronometers.” 

Naturally, the history of marine chronometers didn’t stop at John Harrison’s clocks, however that is where it all began. Though it should be noted that back then, people were looking for the most precise clocks that were available, not that they would meet specific criteria as it is now the case with COSC and METAS which we’re going to discuss below. 

Source: www.wornandwound.com

The Two Principal Certifications: COSC and METAS 

Fast forward many decades, watchmakers could ensure the accuracy of their watches (first, pocket watches and then wrist watches) by entering competitions organized by observatories. The two main observatories were Switzerland’s Neuchâtel Observatory and London’s Kew Observatory through the 19th and a part of the 20th century. As it is often the case in horology, many things changed after the Quartz Crisis and these two observatories stopped running competitions. To replace them, a non-profit agency called the *Contrôle officiel suisse des Chronomètres* (COSC) was formed in 1973 to help measure and award certifications for chronometer precision. The COSC set a standard for accuracy following ISO 3159 indicating that movements had to run within -4/+6 seconds per day, in addition to testing for reliability in different positions and temperatures. 

Source: www.stockx.com

In the past few years, we started seeing the words “METAS Certified” popping everywhere whenever a new Omega watch would be released. METAS, the Swiss Federal Institute of Metrology, in partnership with Omega, created a new certification for accuracy and resistance to high magnetic fields, up to 15,000 Gauss. (To put this number in perspective, the highest resistance to magnetism a watch has ever achieved is in the neighborhood of 33,000 Gauss.) Each Omega movement which passes the tests is awarded the Master Chronometer certification, setting the new standard for accuracy and reliability in the world of Swiss horology. Though, it should be noted that only Omega watches can be awarded this certification since Omega is closely related to METAS. 

Source: www.omegawatches.com

Other Standard of Chronometer Certifications 

Besides COSC and METAS, other brands, and countries, set their own standards for superior accuracy. Rolex created the “Superlative Chronometer” label many years ago, however in 2015, the brand updated its requirements so that movements displaying these words need to run at -2/+2 seconds per day. Furthermore, the brands that fall within the Fleurier family (Chopard, Parmigiani, and Fleurier) follow their own Qualité Fleurier Standard (Fleurier Quality Foundation or FQF) which requires, amongst other things, that a watch be 100% made in Switzerland, showcases certain levels of finish, and can resist their own shock and magnetism resistance tests and tick at 0/+5 seconds per day afterwards. Additionally, Patek Philippe created its own standard of quality and other countries, Germany for example, follow their own guidelines as well. (In the latter case, standard DIN 8319.)

Source: www.monochrome-watches.com

Final Thoughts 

As we saw above, there are many ways to get a watch chronometer certified. However, this is only possible as long as the watch is made in the right country. The COSC certification, for example, can only be awarded to movements made in Switzerland, as it is the case, I believe, for the METAS certification as well. And while many watch collectors and professionals are glad to see the word “Chronometer” printed on the dial of their favorite timepieces, I’ll be honest with you: many Japanese made movements from Miyota and Seiko are as accurate as many COSC certified Swiss made movements right off the box. In my experience, a top grade Sellita SW300-1 performs as well as Rolex caliber in a watch that costs multiple times more. However, I do get the attraction of getting a movement officially certified as being accurate, and I indulge in that pleasure from time to time.