Collectors often admire when a Datejust takes on a look that feels both familiar and unexpected, and the Rolex Datejust 31 178240 White Roman Dial with diamond bezel is a perfect example. While the factory version came with a simpler smooth bezel, this configuration brings in details that change the character completely – a White Roman dial that’s crisp and easy to read, paired with a diamond bezel that frames the display with brilliance. Built in stainless steel, it keeps the resilience of an everyday watch, but the added sparkle shifts it into a piece that feels special whenever it’s on the wrist.
Before diving into the fine details, it helps to understand where the Datejust 31 fits within Rolex history.
The Story Behind the Rolex Datejust 178240
The Rolex Datejust first appeared in 1945 as the world’s first self-winding chronometer wristwatch to feature a date window on the dial at 3 o’clock. By the 1950s, Rolex refined the mechanism so the date switched more quickly at midnight, giving the Datejust a detail that became a trademark.
The 31mm case size (as seen on the reference 178240) appealed to those who wanted something smaller than the classic 36mm Datejust but still large enough for the dial and date display to remain clear. It gave collectors and everyday wearers an option that balanced presence and comfort.
From the factory, the 178240 came in Oystersteel with a smooth domed bezel, paired with dials in choices such as White Roman, silver, pink, or blue. Roman numerals and baton markers were both offered, and the model was typically matched with the Oyster bracelet, with Jubilee also available.
The reference 178240 was originally delivered with a smooth steel bezel, which was the standard option for this model. Rolex does offer factory diamond bezels in other Datejust references, especially in the 36mm line, but the 178240 was most commonly seen with its clean, polished steel finish. Over time, collectors and jewelers introduced diamond bezels to this reference, adding extra sparkle while keeping the watch’s familiar Datejust identity intact. Paired with the factory White Roman dial, the diamond bezel brings a brighter frame that makes the numerals and hands easier to notice on the wrist.
From context to construction, we move now to the case and bracelet that complete the Datejust 178240’s foundation.
Oystersteel Strength Meets Diamond Detail
The 31mm Oystersteel case of the Datejust 178240 is high-polished on the lugs and case sides, giving it a bright, mirror-like finish that complements its size. The back of the watch is a solid closed caseback in steel, designed for durability and a secure seal. A screw-down crown, high-polished and signed with the Rolex coronet, further protects the movement inside. Made from solid steel with a sealed back and crown, the case is designed to stay secure against water and daily wear. It delivers a water resistance of 100 meters (330 feet) – more than enough for everyday security, even though most owners will wear this piece as a luxury watch rather than a sports model.
Framing the dial is a circular diamond bezel, with stones set evenly around the case to form a continuous ring of sparkle. Compared to the smooth steel bezel the 178240 was originally issued with, this addition brings a brighter and more noticeable presence. The diamonds enhance the outline of the watch while still suiting its 31mm size, giving the Datejust a touch of elegance that feels natural on the wrist.
Securing the watch is the Oyster bracelet in stainless steel, designed with brushed outer links and high-polished center links. The high-polished sides of the bracelet flow naturally into the high-polished case sides, creating visual harmony across the watch. It closes with the Oysterclasp (designed with the same brushed outer links and high-polished center finish as the bracelet) and includes the 5mm Easylink extension system for quick adjustments to wrist size throughout the day.
Having explored the case and bracelet, we can now turn to the most captivating feature: the dial.
The Rolex 178240 Dial: Classic Style with Subtle Detail
The White Roman dial of the Datejust 178240 stands out for its crisp, classic look. The applied Roman numerals, made of polished white gold, not only resist tarnish but also play with light in interesting ways. In bright light, they shine with a silvery tone, while at other angles they appear almost black, giving the dial a subtle variety. At 12 o’clock, the applied Rolex crown logo anchors the display, with the ROLEX text neatly printed beneath it, while the small “SWISS MADE” at 6 o’clock confirms its origin.
Unlike other Datejust dials, this version features no luminous material, keeping the display clean and classic. The hour, minute, and seconds hands are also made of high-polished white gold, ensuring long-lasting shine and matching the finish of the numerals.
At 3 o’clock, the date window sits beneath the Cyclops lens, which magnifies the numeral for easier reading at a glance. Surrounding it, the circular diamond bezel adds light and contrast to the dial, making the Roman numerals and high-polished hands stand out more clearly against the white background. With its clear date display and diamond bezel, the dial shows how function and style can work together in one watch.
Now that we’ve explored the dial, it’s time to look beneath the surface at the movement that keeps the Rolex Datejust 178240 running.
Rolex Caliber 2236: Accuracy and Practical Functions
Powering the Datejust 178240 is the Caliber 2236 automatic movement, one of the Rolex most modern midsize calibers. It features a self-winding Perpetual rotor, which means the watch keeps itself charged as long as it’s on the wrist, while also allowing manual winding through the crown when needed.
At its core is Rolex’s Syloxi silicon hairspring, designed to resist the effects of magnetism and temperature changes – two factors that often disrupt accuracy in traditional hairsprings. Supporting it are Paraflex shock absorbers, helping the movement stay stable against the small bumps and vibrations of daily wear.
For everyday usability, the movement includes both a stop-seconds (hacking) function, allowing precise synchronization when setting the time, and a quickset date feature, so the calendar can be adjusted independently of the hands.
Each Caliber 2236 is tested under the Rolex Superlative Chronometer certification, guaranteeing accuracy within +2/-2 seconds per day once cased. Combined with a 55-hour power reserve, the watch can be set aside for most of a weekend and still be ready to go by Monday.
Technical details aside, the Datejust 178240 also shines in how it feels day to day on the wrist.
Wearing the Datejust 178240: What to Expect
At 31mm, the Datejust 178240 sits comfortably on the wrist, making it well-suited for those who prefer a watch that’s smaller than the 36mm Datejust but still substantial enough to notice. The Oyster bracelet curves smoothly to the wrist, with solid links that move easily and avoid hair-pulling. The Easylink extension allows a quick 5mm adjustment, which is useful when your wrist feels tighter in warmer weather or looser in cooler conditions.
The switch from a smooth steel bezel to a diamond-set bezel gives the watch a brighter outline that’s easy to see in both indoor lighting and daylight. Combined with the White Roman dial, the overall look is clean, readable, and slightly more eye-catching than the factory version. It is a watch you can wear every day, whether with a shirt at work or a simple outfit on the weekend, without feeling out of place.
Having experienced how it fits and wears, let’s now bring all of its highlights together in a quick overview.
Rolex Datejust 31 White Roman Dial Diamond Bezel Specs
| Category | Details |
| Case | 31mm Oystersteel |
| Case Details | High-polished lugs and sides, solid steel construction with screw-down crown, 100m water resistance |
| Bezel Details | Circular diamond bezel (aftermarket upgrade, replacing the original smooth steel bezel) |
| Caseback | Solid closed steel caseback |
| Bracelet | Oyster bracelet in stainless steel with brushed outer links, high-polished center links, and high-polished sides |
| Crystal | Scratch-resistant sapphire with Cyclops lens over the date |
| Dial | White Roman dial |
| Dial Details | Applied white gold Roman numerals (appear dark at angles), polished white gold hands, applied Rolex crown at 12, ROLEX text below, “SWISS MADE” beneath Roman VI, no lume |
| Clasp | Oysterclasp with high-polished center and brushed outer finish, 5mm Easylink extension system |
| Movement | Caliber 2236 automatic, Syloxi hairspring, Paraflex shock absorbers, stop-seconds and quickset date, Superlative Chronometer certified, 55-hour power reserve |
| On-Wrist Feel | Comfortable 31mm fit, smooth bracelet links that avoid hair pulling, bezel adds brightness, versatile for daily or occasional wear |
Now that the specs are clear, let’s wrap up with why this model continues to be a favorite among collectors.
Why the Rolex Datejust 178240 Could Be Right for You
It isn’t about collecting for the sake of rarity, nor about chasing trends. It’s about wearing something that feels right on the wrist, a watch that reflects good taste and carries a touch of character that makes it stand apart. For many, that’s what makes a watch feel truly personal.
The Datejust 178240 in this configuration is a piece that can move with you – from daily office wear to an evening out or even relaxed weekends. It’s versatile, comfortable, and stylish in a way that doesn’t need explanation. If you’re looking for a watch that can match different parts of your lifestyle while still feeling special each time you put it on, this one deserves serious consideration.
Want a better view of the Rolex Datejust 31 178240?
Check out our video tour of its White Roman dial and diamond bezel here.
