Rolex Datejust 31 Gold — Mother-of-Pearl Diamond Dial | Ref. 178245

Reference 178245 is a Datejust 31 in 18 ct gold with a mother-of-pearl dial set with diamond hour markers — a specification that places it firmly in the upper tier of the mid-size Datejust family. Mother-of-pearl as a dial material has a particular significance in fine watchmaking: sourced from molluscs and processed to produce uniformly thin, translucent sections, it introduces an organic luminosity that no painted or printed dial can approximate. The iridescence shifts as the viewing angle changes, giving the 178245 a quality of perpetual novelty despite its classical design language.

The 178xxx reference series designates the Calibre 2235 — the predecessor to the current 2236 — which powered the Datejust 31 before the movement generation was updated. The 2235 is an accomplished self-winding manufacture movement with a Parachrom hairspring, running at 28,800 vph and delivering reliable daily performance within COSC parameters. The gold case — whether yellow, white, or Everose depending on the sub-variant — is finished to Rolex's customary combination of polished and brushed surfaces, and the President or Jubilee bracelet in matching gold provides the appropriate setting for a precious-metal piece of this specification.

For buyers in the secondary market, 178245 references in excellent condition with original dials command a premium that reflects both the material cost of the gold case and the decorative integrity of factory-set dials. The transition from Calibre 2235 to 2236 makes this reference a slightly earlier-generation piece, but that distinction matters little in practical terms — Rolex's service network supports both calibres comprehensively, and the 2235's performance record is long-established.