The story behind the Patek Philippe 5100 is that Patek has always had a tendency to make commemorative watches to mark important anniversaries and milestones, like their own 100 year birthday, or long standing important partnerships like the special edition watches for Wempe and Tiffany. The reference 5100 was made to commemorate the turn of the century in 2000. Given the important occasion, they brought out the first 10 day power reserve movement ever created by any manufacturer, ever, in a wristwatch. Further, Patek used this unique case shape, which was inspired by the manta ray. In fact, when you open the book that comes with the watch, there is a two page color photograph of a manta ray.
The reference 5100J was produced in a limited edition of 1500 pieces.
The case is 18k gold with dimensions of 46mm long by 34mm wide. Front and back crystals are sapphire. The case finish is polished. The crown is protected by the shoulders surrounding it.
Movement is the manual winding Patek Philippe Caliber 28-20 with 29 jewels, many of which are in gold chatons, free sprung Gyromax balance which is adjusted to heat, cold, isochronism and in 5 positions, and is stamped with the Geneva Seal. The 10 days of power reserve are provided by twin barrels.
Dial is matte creamy white silver with applied gold hour markers and arabic numerals, gorgeous gold dauphine hands, a subsidiary seconds dial and 10 days power reserve indicator.
Strap is the original, new Patek Philippe black crocodile with gold Patek tang buckle.
The watch is new and is complete with the “Watches To Mark The Third Millennium” hardcover book, along with the original documents (Certificate, Attestation of limited production, Registration document, original Chronometer Certification) and placard with solid silver medallion commemorating the Third Millennium with plastic base to stand the placard up in.