Rolex Datejust 31 White Rolesor — Silver Index Diamond Bezel Dial | Ref. 278384RBR

Reference 278384RBR belongs to the current-generation Datejust 31 lineup and is distinguished by its fully diamond-set bezel alongside a silver dial carrying applied index hour markers — a pairing that emphasizes brightness and light return over the more decorative Roman or dial-set diamond configurations. The RBR suffix in the model number designates the diamond-set bezel, confirming that this is a factory Rolex specification rather than an aftermarket modification, a distinction that carries significant weight for collectors and buyers concerned with originality. The 31 mm Oyster case occupies a versatile size bracket suited to a range of wrist proportions.

The Calibre 2236 is the movement within this reference, Rolex's proprietary self-winding calibre for the 31 mm Datejust and Pearlmaster families. Its most significant technical feature is the Syloxi hairspring, manufactured from silicon in-house by Rolex — offering greater resistance to shocks and magnetic fields than conventional metallic hairsprings while requiring no lubrication at the escapement. A bidirectional rotor winds the mainspring efficiently, and the movement carries chronometer certification. The White Rolesor case pairs a stainless steel body with 18 ct white gold bezel housing, crown, and coordinating bracelet components, delivering the hallmarks of precious metal in a durable format.

For the secondary market buyer, the factory diamond bezel is the defining value attribute of this reference. Aftermarket diamond bezels are widespread in the Datejust segment, and the premium commanded by factory-set examples is both rational and consistent. The silver index dial is a clean, versatile choice that does not compete visually with the bezel's brilliance, making the overall composition balanced. Original documentation confirming the RBR specification is particularly important when purchasing pre-owned.