The Patek Philippe reference 2451 was introduced in 1949 and produced for 9 years. Manufactured as a water-resistant version of the Patek Philippe Calatrava reference 96, it featured the same 3mm diameter case and elegant long lug design distinctive to this classic line of watches. This particular example is in rose gold with a pink dial, commonly known as a 'Pink On Pink' configuration which was often destined for the South American or Spanish market. The Patina: The darkening of the dial over time has likely been caused by the gradual ingress of moisture, possibly from a humid environment. Although the case was water resistant, over the decadesit is still possible for moisture to penetrate and cause a discolouration of the dial pigment. There is also evidence of streaking surrounding the markers which may be the eventual result of a cleaning agent having been applied to the dial at some stage during a service.
