One of the big stars in Rolex’s 2018 collection is the new Oyster Perpetual Cosmograph Daytona, adorned with gemstones. In place of the emblematic tachymetric scale, the bezel features a gradation of 36 baguette-cut sapphires in rainbow hues. Eleven baguette-cut sapphire hour markers each match the colour of the corresponding gemstone on the bezel. The traditional chronograph counters are in pink gold crystals. Moreover, the case is embellished with 56 brilliant-cut diamonds set into the lugs and crown guard. On display in this watch is the full range of Rolex’s excellence in gem-setting.

Whether for diamonds, sapphires, rubies or emeralds, Rolex is a master at the art of gem-setting. To adorn its timepieces with the most striking gemstones, the brand has its in-house gemmologists and gemsetters. Gemmologists are responsible for examining and selecting the gemstones received, retaining only those that meet Rolex’s extremely stringent quality criteria. The stones then pass into the hands of the gem- setters, who are tasked with placing and fixing each stone to best reveal its beauty, colour and sparkle. Rolex has offered gem-set watches throughout its history. In embellishing its watches with precious stones, the brand endows them with an alternative aesthetic, while conserving their identity and all their technical features, such as reliability, robustness, and resistance to magnetic fields and shocks.

Rolex uses only the highest quality natural stones. Upon their arrival at the ateliers, all gemstones – both diamonds and coloured stones — undergo rigorous verification procedures. To guarantee the quality of the stones, gemmologists have a range of analysis tools at their disposal, in addition to their expertise. These tools, some of which are specially developed for Rolex, can provide information on the stones’ chemical composition. Diamonds, for example, are systematically tested via X-ray imaging to confirm their authenticity.

The way in which the gemstones are cut — the symmetry and shape of the facets – determines the way in which light penetrates the stones and is reflected off the pavilion or lower part of the diamond. The cut therefore directly influences a stone’s brilliance. In the case of diamonds, a well-cut stone accentuates the intensity and number of reflections, even creating rainbow hues. The facets of each of the stones — the result of the diamond cutter’s painstaking work – are analysed in the gemmology laboratory. Clarity relates to the absence of inclusions in a stone. Rolex selects only the most translucent natural gemstones. For diamonds, IF (Internally Flawless) stones alone are accepted – those in the highest category of the grading scales generally used in gemology.

The colour of the diamond is always evaluated by the naked eye and calls for reasoned judgement. In their assessment, expert gemmologists compare the diamonds against certified master stones. The brand chooses to use only the most colourless diamonds; they must fall within categories D to G — the highest grades on the Gemological Institute of America colour scale. This meticulous and rigorous analysis carried out according to the brand’s quality criteria, ensures that all the gemstones on a watch are uniform, and of the very best quality.

Once approved by the gemmologists, the precious stones are then entrusted to the gem-setters. With the precision of a watchmaker, they set each stone, one by one, onto the watches. A gem-setters craft is multifaceted. First, decisions are made with designers in the Creation Division about the colours and arrangement of the stones. This is a subtle exercise in finding a balance between aesthetic and technical requirements. Then follows consultation with the case and bracelet engineers. Together they study the future placement of the stones to prepare, to the nearest micron, the gold or platinum into which the stones will be set. For each stone, they determine the precise amount of metal required to hold it in place.

The gem-setter then patiently sets the stones individually to achieve a perfect harmony of colours and reflections and find the optimal position. Rolex tolerances are to within no more than two-hundredths of a millimetre, which is around a quarter of the diameter of a human hair. The surrounding metal is then gently pushed into place around the stones to fix them securely. The skill of the gem-setter is showcased in their ability to choose the appropriate tool, to find the right angle, and to apply the correct amount of force – a step repeated up to almost 3,000 times on some diamond- paved dials. A final polish makes the tiny metal settings shine, intensifying the watch’s splendour.