Datejust 31 Yellow Gold Fluted / Oyster / Black MOP

About This Watch

The Rolex Datejust 31, in its 178278-0113 iteration, embodies the quiet authority of a timepiece that has defined elegance since its introduction in 1945. The yellow gold fluted case, a hallmark of the Datejust lineage, is rendered with a precision that underscores the collection’s enduring role as a symbol of understated sophistication. The dial, a deep black mother-of-pearl surface, is framed by gem-set indexes that catch light with subtle, deliberate brilliance, while the stick hands trace their path with the clarity of a well-worn path. This reference retains the Datejust’s signature 18-carat gold bezel, its fluted edges a nod to the brand’s early 20th-century innovations in case design, and the sapphire crystal ensures the dial remains unmarred by time or circumstance. At its heart lies the Caliber 2235, a self-winding movement with a 70-hour power reserve, featuring the brand’s advanced Chronergy escapement and Parachrom balance spring. These elements, combined with the 100-meter water resistance and the Oyster case’s seamless construction, reflect Rolex’s commitment to marrying horological precision with everyday durability. The closed case back, though discreet, invites contemplation of the engineering within—a quiet testament to the brand’s mastery. This watch is for those who seek a companion that transcends trends, a piece as suited to a boardroom as it is to a gala. It is not a statement, but a legacy in the making.

In Context

At 31 mm it is small by current standards, in the range most wristwatches occupied before cases began growing through the 1990s. The case back is closed, so the movement stays out of sight, and the sapphire crystal will resist everything short of deliberate abuse. 100 m is genuine swimming resistance — more than the shape of this watch suggests it would need.

The movement winds itself from the motion of your wrist. 48 hours of reserve is enough to set it down on Friday evening and find it still running on Monday. At 28,800 vph the seconds hand advances 8 times a second.

178278-0113 is one of 37 executions of the 178278 base reference. Underneath they are the same watch; what separates this one is a black dial and a yellow gold case.

Rolex

White · Yellow Gold

178278-0010 · 31 mm

Rolex

Champagne · Yellow Gold

178278-0018 · 31 mm

Rolex

Champagne · Yellow Gold

178278-0021 · 31 mm

Rolex

Champagne · Yellow Gold

178278-0025 · 31 mm

Rolex

Silver · Yellow Gold

178278-0028 · 31 mm

Rolex

Silver · Yellow Gold

178278-0031 · 31 mm

Rolex

Silver · Yellow Gold

178278-0034 · 31 mm

Rolex

Silver · Yellow Gold

178278-0037 · 31 mm

+ 28 more variants in this family.

The 2235 is the small Rolex automatic of the six-digit generation, a 20 mm movement with a date. It carried the Datejust 31 and the 26 mm Lady-Datejust from around 2000 until the 2236 replaced it. It powers 733 watches in this library. It has 31 jewels, a 48-hour reserve and a beat of 28,800 vph, and every one is a COSC chronometer. It is the same architecture as the [2236](/calibers/rolex-2236) that followed, without the silicon Syloxi hairspring and with seven hours less reserve; the [2236 piece](/blog/the-rolex-2236-the-most-common-movement-in-this-library) explains what changed. The library finds it almost entirely in the [Datejust 31](/brands/rolex/datejust-31): 682 references, the 1782xx generation, whose 45 base references and hundreds of dial variants make that collection the largest here. The 26 mm [Lady-Datejust](/brands/rolex/lady-datejust) of the 1791xx generation accounts for 29, the [Pearlmaster](/brands/rolex/pearlmaster) 29 mm and 34 mm for 19, and the 35 mm Yacht-Master for 3. A six-digit Datejust 31 reference is a 2235; the seven-digit one is a 2236, as the [reference-number guide](/blog/how-to-read-a-watch-reference-number) explains. The 2231 was its no-date sibling in the Oyster Perpetual, and the [3135](/calibers/rolex-3135) its counterpart in the 36 mm cases.

732 other watches in the library run the Rolex 2235.

Rolex

Datejust 31 Yellow Gold Diamond / Oyster / Black MOP

178158-0056 · 31 mm

Rolex

Datejust 31 Stainless Steel Diamond / Oyster / Pink MOP

178384-0061 · 31 mm

Rolex

Datejust 31 Rolesor Everose Domed / Jubilee / Black MOP

178241-0043 · 31 mm

Rolex

Datejust 31 Yellow Gold Domed / Oyster / Champagne Roman

178248-0079 · 31 mm