Cerachrom

Cerachrom is Rolex's proprietary ceramic bezel insert material, introduced in 2005 on the GMT-Master II reference 116718LN. It progressively replaced the aluminium bezels of earlier sports models: the Submariner switched in 2010, the Daytona in 2011, the two-tone GMT references in 2014.

Why ceramic

Anodised aluminium bezels — standard on Rolex sports models from 1953 to the mid-2000s — had two structural weaknesses:

• Scratch sensitivity. Aluminium is soft; an accidental knock against a door frame leaves a visible mark.
• Fading. UV exposure shifts anodised aluminium colour over years. The "ghost" bezels collectors now hunt — faded Submariner inserts — originally appeared as a service issue, not a design intent.

Ceramic solves both. Under normal wear Cerachrom is essentially scratch-proof; only diamond or another ceramic abrasive leaves traces. Colour is part of the material matrix, not a surface layer, and remains stable under UV.

How it is made

The ceramic is sintered at high temperature. The scale — 24-hour, dive minute track, or tachymeter — is then engraved into the surface. The engraving is filled with platinum or gold via PVD deposition; the numerals catch light differently from the surrounding ceramic and remain readable for the life of the watch.

Two-tone variants

Pepsi (red-blue, BLRO), Batman (black-blue, BLNR), Coke (red-black), Root Beer (brown-black), Sprite (green-black) — all two-tone Cerachrom configurations. The manufacturing challenge is joining two ceramic colours without a visible seam. Rolex fires the bezel as a single colour, then chemically converts one half to the second colour. The Pepsi GMT-Master II 116719BLRO of 2014 was the first commercial two-tone Cerachrom bezel.

What it means on the secondary market

Pre-Cerachrom references (aluminium bezels) are increasingly collected. A 116710LN — a standard production GMT in its day — is now a transitional piece. Its direct predecessor, the aluminium-bezel 16710, sits squarely in the vintage segment with a growing premium.

At our atelier in Munich we see both generations every day. When servicing or buying a pre-Cerachrom reference, we leave the original bezel in place if the patina is homogeneous — character lives there.

Beyond Rolex

Omega, Tudor, Breitling and others also use ceramic bezels. "Cerachrom" specifically is a Rolex SA trademark. If a listing says "Cerachrom," the watch is a Rolex — otherwise it is a different ceramic composition.