Audemars Piguet 26579CE (New with box and papers) — USD 259,000 on eBay

The Audemars Piguet Royal Oak Perpetual Calendar reference 26579CE represents a significant milestone in the brand's use of advanced materials, being the first full ceramic Royal Oak Perpetual Calendar. It integrates a highly complex perpetual calendar complication within the iconic Royal Oak architecture, presented in a contemporary and durable material. This reference features a 41mm black ceramic case and bracelet, paired with a 'Grande Tapisserie' dial. The self-winding Caliber 5134 movement, visible through a sapphire case back, provides the perpetual calendar functions including day, date, moon phase, astronomical moon, month, leap year, and week indication. The movement operates at 19,800 vph and offers a power reserve of approximately 40 hours. For collectors, the 26579CE holds importance as a pioneering piece in Audemars Piguet's ceramic offerings, combining traditional haute horlogerie with modern material innovation. Its introduction marked a new chapter for the Royal Oak Perpetual Calendar line, influencing subsequent ceramic models and solidifying its place as a notable reference within contemporary watchmaking.