Produced exclusively in solid 18-karat gold (Au750) or 950 platinum (Pt950)—never in stainless steel—the 40mm Rolex Oyster Perpetual Day-Date 40 weighs 208.2g in 18K Yellow Gold (Ref. 228238), 209.6g in 18K Everose Gold (Ref. 228235), 212.5g in 18K White Gold (Ref. 228239), and 256.4g in 950 Platinum (Ref. 228236), anchored by its ceramic-sleeved semi-circular three-piece President bracelet and Calibre 3255.
Key Quantitative Laboratory Takeaways
- Unlike any other sports watch, the Rolex Day-Date has never been manufactured in stainless steel since its 1956 debut; every authentic President is solid Au750 or Pt950.
- The modern 40mm President bracelet embeds high-tech ceramic sleeves around the internal solid gold link pins, completely eliminating the "bracelet stretch" that plagued vintage 36mm references.
- Calibre 3255 delivers a 70-hour power reserve and an instantaneous midnight double-jump of both the full-spelled Day aperture at 12 o'clock and the Cyclops Date at 3 o'clock.
- Signature dials include the 60th-Anniversary Olive Green Roman (Ref. 228235 / 228239), Champagne Baguette (Ref. 228238), Natural Eisenkiesel, Black Onyx, and Ice-Blue (Ref. 228236).
| Reference Code | Precious Metal Alloy | Bezel Architecture | Iconic Dial Pairings | Verified Mass (g) | Calibre |
|---|---|---|---|---|---|
| Ref. 228238 | 18K 3N Yellow Gold (Au750) | Diamond-Cut Fluted 18K Bezel | Champagne, Green Ombre, Black Onyx | 208.2g | Cal. 3255 |
| Ref. 228235 | 18K Everose Rose Gold (Au750) | Diamond-Cut Fluted 18K Bezel | Olive Green, Slate Ombre, Eisenkiesel | 209.6g | Cal. 3255 |
| Ref. 228239 | 18K Palladium White Gold | Diamond-Cut Fluted 18K Bezel | Olive Green, Blue Roman, Meteorite | 212.5g | Cal. 3255 |
| Ref. 228236 | 950 Ruthenium Platinum (Pt950) | Machine-Fluted Pt950 Bezel | Glacial Ice-Blue Roman / Baguette | 256.4g | Cal. 3255 |
| Ref. 228348RBR / 345RBR | 18K Yellow / Everose Gold | 48 Brilliant-Cut VVS Diamonds | Diamond Pave, Mother-of-Pearl, Rubies | 209.8g | Cal. 3255 |
| Ref. 228398TBR / 395TBR | 18K Yellow / Everose Gold | 40 Trapezoid Baguette Diamonds | Meteorite Baguette, Turquoise, Green | 211.0g | Cal. 3255 |
Why the Day-Date 40 Is Never Made in Steel and Always Weighs Over 208 Grams
Since its introduction in 1956 as the first waterproof self-winding chronometer to display the day of the week spelled out in full at 12 o'clock, the Rolex Day-Date has maintained an unbroken rule: it is crafted exclusively in solid 18-karat gold (Au750) or 950 platinum (Pt950). Consequently, the moment a collector lifts a Day-Date 40 Ref. 228238 or Ref. 228235, the 208.2-gram to 212.5-gram mass of the fluted bezel, Oyster middle case, and semi-circular three-piece President bracelet immediately distinguishes it from any steel timepiece.
How Ceramic Pin Inserts Inside the President Bracelet Prevent Stretch
On vintage 18K gold Day-Date bracelets produced between the 1960s and 1990s, fine dust particles entering between the gold link pins and the soft 18K gold link bores acted as an abrasive paste, gradually elongating the holes and causing "bracelet stretch." On the modern Day-Date 40 Ref. 228238, 228235, and 228239 in our Monte-Carlo Register, microscopic high-tech ceramic tubes encase each solid gold connecting pin inside the semi-circular links, preventing metal-on-metal wear while giving the concealed Crownclasp a crisp, zero-play articulation.
| Architectural Feature | Day-Date 40 (Ref. 228238 / 228235) | Legacy Day-Date II (Ref. 218238) | Day-Date 36 (Ref. 128238) |
|---|---|---|---|
| Case Diameter & Lug-to-Lug | 40.0 mm x 47.4 mm (Refined Proportion) | 41.0 mm x 49.5 mm (Broad Bezel) | 36.0 mm x 43.2 mm (Classic Dress) |
| Full-Bracelet 18K Gold Mass | 208.2g – 212.5g (24 President Links) | 218.0g – 221.0g | 178.5g – 182.0g |
| Internal Ceramic Pin Inserts | Yes (Zero Stretch Over Lifetime) | No (Metal-on-Metal Pin Friction) | Yes (Added in 1282xx Generation) |
| Movement & Power Reserve | Calibre 3255 (70 Hours) | Calibre 3156 (48 Hours) | Calibre 3255 (70 Hours) |
| Roman Numeral Construction | Deconstructed 10-Piece Faceted 18K Gold | Single-Piece Stamp Applied Numerals | Faceted 18K Gold / Baguette Markers |
Deconstructed 18K Gold Roman Numerals and Calibre 3255 Midnight Double-Jump
Inspecting the Olive Green dial of the Everose Ref. 228235 or the Ice-Blue dial of the Platinum Ref. 228236 under a loupe reveals that each Roman numeral (such as IIII, VI, or VIII) is not a single stamped piece, but an assembly of individual diamond-faceted 18K gold bars hand-riveted onto the sunburst dial plate. Beneath the dial, the cloned Calibre 3255 stores energy in a spring-loaded cam throughout the evening and triggers an instantaneous, synchronized click of both the Day and Date discs within two milliseconds of midnight.
Explore Verified Rolex Solid 18K Gold References in Our Register
Every timepiece referenced in this monograph is available for immediate allocation with pre-shipment 4K Mettler-Toledo gram weighing, Fischer XRF Au750 spectroscopy, and 6-position Witschi Chronoscope certification. Navigate directly to the 18K WATCHES Homepage Master Register, the Rolex Solid 18K Gold Collection Hub, or the Complete 774-Watch Catalogue:
25 Years in Monte-Carlo & Geneva Collector Horology, Author of The Sovereign Precious-Metal Watch Index.
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