It is possible to read this watch by one numeral. The enlarged six sits at the bottom of the dial set with diamonds while the other eleven are plain, and once the eye has found it the rest of the sequence follows by position rather than by being read, which is a genuinely different way of telling time from a dial where every marker is equal. Reference 278344RBR is the 31mm Datejust in a combination of stainless steel and white gold with a domed bezel set with diamonds, and this configuration pairs that aubergine dial with the Jubilee bracelet. Very few dials are built to be read in that order.
The dial is an even lacquer applied in several thin coats to hold its tone across a curved surface, deep enough that it reads as a near-neutral in most light and resolves as purple only in direct light or against something white. Rolex sets the stones into the numeral itself rather than around it, following the shape of the letterform so it stays readable, and the enlargement is what makes the setting possible since a standard VI would not carry enough stones to register at this scale. Against a dark ground the settings nearly disappear and the stones read as light rather than as mounted objects. The case is a combination of stainless steel and white gold, the least visible two-metal pairing Rolex makes, and the bezel is white gold set with diamonds, so the stones cover most of the only surface where the second metal would otherwise be identifiable. The Jubilee contributes five links across the width with white gold center rows between steel outer links, and because the two metals sit so close in color the alternation reads as a change of finish rather than of material, which is not true of any Everose or yellow gold pairing. The date sits at three under the Cyclops lens on a matched disc, displacing the numeral that would otherwise occupy that position. The hands are polished white gold and drawn short of the numerals so they cross without appearing to touch them, and Rolex redraws them for each case size rather than carrying one set across the range. The date frame is polished white gold set flush with the dial so the aperture belongs to the surface. The contrast between the set numeral and the plain ones is wider here than on any other dial in the range, since a deep cool lacquer gives the stones maximum separation while the plain white gold numerals read as restrained metal rather than as light.
The date is the only indication the watch carries beyond the time. Rolex matches the disc to the dial rather than leaving a white window in a dark surface, and the Cyclops lens above it has been part of the Datejust since 1953. A single aperture is also what allows a full Roman sequence to fit at all. The date changes instantaneously at midnight rather than creeping through the surrounding hour, the feature the Datejust introduced in 1945 and the reason it carries its name. Correction runs through the winding crown without advancing the hands, hand winding uses the same crown with no separate position to learn, and nothing the watch asks for requires a tool. The movement is self-winding with a power reserve of approximately 55 hours, engineered into a movement sized for a 31mm case rather than carried down from a larger one, since a smaller barrel stores less and a proportionally smaller rotor supplies less. The crown screws down against the case, and the Jubilee closes with a concealed clasp folded away inside the links. A movement of this size gathers less from the same wrist movement than a larger one, so the watch prefers regular wear.
The Datejust arrived in 1945 as the first self-winding wristwatch to show the date in a window, and the 31mm case sits between the 28mm Lady-Datejust and the 36mm original, which makes it the size for buyers who find one too small and the other too large. The 278000 generation replaced the 178000 series in 2018 with a revised case and bracelet. For most of the model's history the dial range ran to light colors, and aubergine is among the newest of the dark options. The enlarged gem-set numeral appears on a small number of dials across the catalogue and always at six. Within the generation, 278344RBR is the steel and white gold reference with a diamond-set domed bezel. The 31mm case is the least discussed of the three Datejust sizes and has quietly absorbed most of the demand that used to go to the smaller references. Dark dials also reached this size later than they reached the 36mm one. Rolex has never built the enlarged numeral on a dial darker than this one, which makes it the extreme of the three grounds the feature is offered on. Aubergine is never offered plain on this reference, unlike the other two grounds.
This appeals to a buyer who wants the dial to have a hierarchy. Most watches present twelve equal positions and leave the eye to sort them, and this one sorts them in advance, which is why it reads faster than a conventional Roman dial despite being the more decorated of the two. On the Jubilee the wrist supplies its own fine detail, so the watch is busy in two places rather than one, and buyers who find that too much generally take the Oyster version of the same dial. Between the pair this is the more decorative and the more comfortable, since more links across the same width follow a small wrist more closely. It is among the less common configurations on the reference, since aubergine arrived recently and the enlarged numeral dials are built in smaller numbers than the standard Roman ones. It is the version to own if the watch should be read from one point rather than scanned.
