Ref. 3448Produced in 586 examples from 1962-64 to 1982, with the calibre 27-460Q, the majority in yellow gold, rarely in pink or white gold. This series began with the serial number 1?119?000.A similar watch is published in Patek Philippe Wristwatches, by Martin Huber & Alan Banbery, 1998 Edition, p. 288.A unique example of this reference is known to date in platinum. Its movement was made in 1973, and, at the request of the owner, was cased in platinum by Patek Philippe, with sapphire indexes on the dial, and delivered on 9 January 1997. This watch was sold by Antiquorum in Geneva, on April 18-19, 1998, for SFr. 201'500 (US$ 133,100).Ref. 3450Produced in 244 examples from 1981 to 1986, with the calibre27-460QPB, the majority in yellow gold, very few in pink or white gold.- First series with leap year display in red on the dial.- Second series with leap year display in numerals on the dial. Made in very few examples with sapphire crystal back. A similar watch is published in Patek Philippe Wristwatches, by Martin Huber & Alan Banbery, 1998 Edition, p. 290.Poinçons de GenèveThe voluntary quality control of watches at the Geneva Observatory, was established by a law dated November 6, 1886. Conditions were laid down for the attribution and stamping of the Poinçons de Genève, punch-marks designed as the coat-of-arms of Geneva. Pocket watches, or wristwatches which carry the Poinçons de Genève, considered as an equivalent to a Bulletin Officiel de Marche, punched on a bridge and on the main plate of the movement, were qualified to be officially termed ?chronometers?.