Rolex 18K Yellow Gold Day-Date Ref 1803

This Rolex 18K Yellow Gold Day-Date Ref:1803 is rated 8 out of 10. Watch only.

Powered by Rolex’s calibre 1556 “Superlative Chronometer, Officially Certified,” this Rolex Day-Date stands as the final representative of the 1500 series that powered the renowned “President” Day-Date collection. Rolex did not begin manufacturing their own calibres until 1957. Prior to that, movements had been sourced from trusted partners like Aegler. However, a significant shift occurred with the introduction of the 1500 series, marking the first instance where Rolex produced the mechanisms entirely in-house.

Given the unique complication of the Day-Date, it necessitated a dedicated calibre. While the initial two references in the series continued to rely on third-party movements, Rolex had, by 1959, refined the calibre 1555—a variant of the 1530 that incorporated the additional functionality required for the secondary calendar display. The cal. 1555 remained in production from 1959 to 1967, overlapping with its successor, the calibre 1556, which debuted in 1965 for certain models of the Day-Date collection. Though outwardly similar, the primary distinction between these two movements lay in a significant increase in balance frequency. The subsequent calibre adhered to the precedent set by the rest of the 1500 series, boasting a heightened rate of 19,800 beats per hour (BPH). Beyond marginal accuracy enhancement, the increased beat rate fortified the mechanism against shocks.

Furthermore, the cal. 1556 boasted a 26-jewel configuration. While an additional stone adorned the upper end of the center wheel, extra jewels were also present in the calendar function, albeit uncounted in the official tally. Notably, the calibre 1556 was the ultimate iteration in the series to empower the Day-Date timepieces, concluding a chapter of horological excellence.