Roman numerals at two positions only is a marker layout Rolex uses rarely, and this is one of the places it appears. Reference 128399TBR is the 36mm Day-Date in white gold with diamonds set into the bezel and continuing onto the lugs, and this configuration pairs it with a pink opal dial, gem-set hour markers in white gold, and Roman numerals at six and nine also rendered in white gold and set with diamonds. The result is a dial with two vocabularies running at once, numerals in two places and markers everywhere else, on a stone that supplies its own irregularity underneath both. It is the most compositionally complicated dial in the reference and the one that rewards close inspection most.
Pink opal is one of the least common materials Rolex cuts dials from and it behaves unlike any of the others. It is a hydrated silica rather than a crystal, softer than the stones used for most dials and considerably more difficult to work, and the color comes from trace inclusions rather than from any structure in the material. The result is a pale, slightly milky pink that varies across the disc, with faint cloudy passages that no two examples share. Cut thin and mounted, it reads warmer in daylight than under artificial light. Against that ground, the gem-set markers in white gold sit as bright points around the perimeter, and the diamond-set Roman numerals at six and nine give the dial a vertical axis it would otherwise lack, since a stone with no directional grain offers the eye nothing to orient against. The case is 36mm in white gold with the bezel and lugs set with diamonds, which surrounds a warm dial with a cool frame. The bracelet is the President, semi-circular three-piece links in matching white gold with a concealed clasp, and the day aperture at twelve and date at three under the Cyclops lens are cut directly into the opal. The contrast between a warm dial and a cool case is a harder balance than the reverse, because white metal tends to drain color out of anything pale set inside it, and opal survives that treatment better than most soft pinks would.
The day of the week is written out in full at twelve, the date sits at three, and both discs change instantaneously at midnight rather than drifting through the hour on either side. The movement is self-winding, carrying a power reserve of approximately 70 hours. Corrections to both calendar indications are made through the winding crown, without advancing the hands to move a disc, which is the interaction an owner has with the watch most often and the one Rolex has refined most quietly over the generations. The day disc is available in a long list of languages, chosen at the point of order, and remains one of the few genuine ways to specify a production Rolex. The Cyclops lens magnifies the date. On a stone dial the apertures deserve attention for a separate reason, since cutting two windows into a soft, irregular material without fracturing it is a real constraint on which stones Rolex can use at all. The crown screws down against the case and the President clasp folds away inside the links. The hands are polished white gold, which keeps them reading as bright lines against a dial that is neither bright nor dark, and that is a more difficult background for a hand than a solid color would be.
The Day-Date has existed only in gold and platinum since 1956, when it became the first wristwatch to spell the day of the week out in full. Stone dials came to the model in quantity during the 1970s and have returned periodically since, and the current catalogue leans on them more heavily than any period before it. Pink opal belongs to that recent wave rather than to the historical run, and it sits at the difficult end of it, because the material limits how many usable discs a block will yield. The 128000 generation replaced the 118000 series in 2019 with a revised case, a cleaner bracelet taper and a longer running time. Within it, 128399TBR is the white gold reference where the setting extends past the bezel onto the lugs. The diamond-set Roman numerals at six and nine are what distinguish this configuration from the rest of the stone dials on the reference, and that layout appears on only a handful of dials across the whole Rolex catalogue. Soft stones constrain production in a way harder materials do not, since cutting loss is higher and a proportion of finished discs are rejected for flaws that appear only at the final stage. That is part of why stone dials appear and disappear from the catalogue rather than running continuously.
The collector this appeals to is one who reads dials closely. Most gem-set configurations at this level are uniform by design, and a buyer scanning quickly will register them as set and move on. This one does not resolve that fast. The mixed layout, the diamond-set numerals and the variation in the opal itself all reward a second look, and that quality tends to matter more to people who own several watches than to those buying their first serious piece. Pink opal also occupies unusual ground in the catalogue, warm without being loud, and pale enough that the dial reads as a light surface at a distance rather than as a colored one. Paired with a white gold case at 36mm it produces a watch that is heavily specified and still restrained in scale, which is a combination the Day-Date manages better than most. It also sits at an unusual point in the reference, heavily set without being paved, and buyers weighing the stone dials against the paved dial often end up here for exactly that reason.
