Watchmaking certification

What would be the point of a watch if it wasn’t precise? In this respect, a number of brands are determined to prove that their mechanical jewels are only as good as their precision. At their disposal is the Contrôle Officiel Suisse des Chronomètres, a venerable institution whose creation dates back to 1876. Its role? As a neutral, independent body, the COSC issues a chronometric precision certification based on an international standard stipulating a fifteen-day test protocol covering seven criteria. In the end, the rate deviation for a mechanical movement must not exceed the daily values of -4 to +6 seconds per day. If this is the case, it enters the pinnacle of precision watchmaking. Approximately 1.7 million pieces a year are awarded the precious label, representing a fifth of Swiss mechanical watch production. Only a handful of watch brands use the COSC service, with the top four being Rolex, Omega, Tissot and Breitling, which together account for over 80% of the watches bearing this certification.

IN EXTREME CONDITIONS

Breitling is the only Swiss brand to have all its watch movements COSC-certified, including that of the Superocean 44 Special Blacksteel, which is designed for the abyss and guaranteed water-resistant to 1000m.

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WITH FINESSE

A tribute to the very first L.U.C watch to come out of Chopard Manufacture in 1986, this COSC-certified L.U.C XPS 1860 bears the Poinçon de Genève in its rose gold version, a guarantee of quality construction and finish.

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ANTIMAGNETIC

With its calibre 8900 co-axial escapement, this Omega Seamaster Planet Ocean 600 M is Master Chronometer certified, and therefore resistant to magnetic fields equivalent to those of an MRI (± 15,000 gauss) with a precision tolerance of between 0 and +5 seconds over 24 hours.

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ALWAYS MORE

Certified as a Superlative Chronometer, the Oyster Perpetual Rolex Deepsea is water-resistant to 3900m and meets criteria stricter than watchmaking standards, i.e. guaranteed precision with a tolerance margin of -2/+2 seconds per day.

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