The movement is Vacheron’s in-house caliber 2460 QH. This is a 29mm x 5.40mmmovement, running in 27 jewel at 28,800 vph, and carrying the Geneva Hallmark, which, since the requirements were updated in 2008, is awarded by an independent entity known as Timelab. Incidentally, the Geneva Hallmark’s update in 2008 ended a 123-year period in which it had been administered by the Geneva School Of Watchmaking, and also marked the beginning of the implementation for controls for the entire cased watch, rather than just the movement.
Caliber 2460 represents some interesting horological history: It is an evolution of Vacheron Constantin’s very first in-house produced and designedmovement. That movement is the caliber 2450, which Vacheron first introduced in the Patrimony Collection, in 2007. Design of the movement had begun under the administration of Proellochs, and after his retirement in 2005 (after overseeing Vacheron Constantin’s 250th anniversary celebrations) its final production and release were overseen by Vacheron’s current CEO, Juan-Carlos Torres.