The bezel is metal cut to do what the stones on the dial do naturally. Reference 278274 is the 31mm Datejust in a combination of stainless steel and white gold with a fluted bezel, and this configuration carries a silver dial with diamond markers in solid white gold settings and no numerals, on the Oyster bracelet. A diamond breaks light up and returns it in several directions at once because of what it is. A fluted rim breaks light up and returns it in several directions because someone cut facets into it. The watch therefore carries the same optical effect twice, once as a property of a material and once as a piece of machining, and they sit within a few millimeters of each other.
Seeing that requires a dial that stays out of the argument, and silver is the one that does. A lacquered ground would assert a value of its own and the eye would read the dial and the rim as separate zones. A metallic ground behaves the way the settings and the case behave, sweeping as one sheet, so the two light-breaking devices are compared directly rather than across a boundary. The difference between them is then obvious: the stones never go dark and the flutes do, since the shaded faces of a deep cut return almost nothing while a diamond keeps working from every angle. The markers sit in white gold settings close in value to both the stones and the ground, so the mounts nearly vanish and the ring reads as twelve bare points. The fluting began as a functional device, giving a tool purchase to screw the bezel down onto the case, and is now cut and polished purely for the way it catches light. The Oyster bracelet is three broad flat links, brushed across the top with polished flanks, closing on a concealed clasp. The case is polished on the flanks and brushed across the lug tops, the lugs are short relative to the case, and every gold element is solid rather than plated.
The watch does one thing beyond telling the time. The date changes instantaneously at midnight rather than creeping through the hours around it, the function the Datejust introduced in 1945 and the one the model takes its name from. With no numerals anywhere the marker ring runs unbroken except at three, and a single aperture is as much as a ring arranged this way can absorb before it stops reading as one, which at 31mm is the tightest that constraint gets. The disc is silver to match the dial, so the opening reads as a recess in the same metal rather than as a pale square, and the printed numeral inside it is the only genuinely dark mark on the watch and the only element holding a fixed weight regardless of angle. The window and its lens together take up proportionally more of a 31mm dial than of any larger case in the range. The Cyclops lens, fitted to the model since 1953, enlarges the numeral roughly two and a half times, and on a case this small it is proportionally the largest single feature anywhere on the face. Correction runs through the winding crown at a dedicated position and leaves the hands where they are. The movement is self-winding with a power reserve of approximately fifty-five hours, the figure the smaller cases carry rather than the longer one fitted to the 36mm. The crown screws down and the bracelet closes flush against the case.
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 that has always been the model's central size. Rolex registered the name for its steel and gold construction in 1933. The fluted rim is older than the model and began as engineering rather than decoration, which is worth holding alongside the fact that it does the same job as the stones on the dial. One is a solved manufacturing problem that turned out to look good and the other is a material chosen because it looks good, and the watch carries both without either being aware of the other. Set dials are tied to the metal of the case, since the markers sit in gold mounts, which is why the decorated faces at every size live on references bringing gold into the case rather than on the all-steel ones. That constraint explains the shape of the catalogue better than any styling decision does, since it settles which references can carry a decorated face before anything about taste is considered, and it is why a buyer wanting stones on a dial has already narrowed the range to the two-tone and solid gold watches without having made that choice deliberately.
The buyer for this wants stones without a stone-set watch. The markers are real and they are diamonds, but they sit on a metallic ground where they read as points of light rather than as jewelry, and the rim above them is a texture rather than a second ring of stones. From any distance the piece is a plain silver two-tone Datejust with a fluted bezel. In the hand it is a gem-set dial. Very few configurations manage that gap and this is the widest of them on the reference. The Oyster is the flatter and more structural of the two bracelets and keeps the whole watch on that footing. A metallic dial shows marks less than a lacquered one, the gold is solid rather than plated, and the flutes hold dust in their grooves in a way a smooth rim does not. A soft brush deals with that, and it is the only upkeep either the rim or the settings ever asks for.
