This year has been exceptionally rich in groundbreaking horological discoveries. The recent sale of the J. Player & Son's Hyper-Complication at Phillips Geneva, fetching nearly $2.8 million, and Derek Pratt's pocket watch for Urban Jürgensen, which realized $4.6 million last year, were remarkable. While these were celebrated pieces, there's a unique allure to uncovering previously unknown treasures. The forthcoming auction at Sotheby's in New York promises to unveil such a marvel: the 'Grosse Pièce,' a pocket watch from the extraordinary collection of the late Robert Olmsted. This timepiece is poised to redefine our perception of horological history, offering unprecedented insights into the craftsmanship of a bygone era.

Sotheby's Unveils Audemars Piguet's 'Grosse Pièce' Masterpiece

On December 8th, in the bustling heart of New York, Sotheby's is set to host an auction that promises to captivate the horological world. Among the star attractions from the esteemed collection of the late American watch enthusiast, Robert Olmsted, is the 'Grosse Pièce'—Audemars Piguet's most complicated pocket watch still residing in private hands. This monumental timepiece, alongside other previously undiscovered Patek Philippe watches and a Patek desk clock that rivals even those crafted for titans like James Ward Packard and Henry Graves, stands as a testament to Olmsted's discerning eye and profound impact on horological history.

The 'Grosse Pièce,' affectionately named the "Large Piece" by its creators, holds a distinguished position, sharing the title with AP's "Universelle" as the most complex pocket watch ever produced by the brand. What sets this particular piece apart is its unique inclusion of a sky chart complication—a singular feature in AP's pocket watch lineage—and its distinction as the only known tourbillon pocket watch from that era. While its counterpart, the Universelle, is proudly displayed at the Audemars Piguet museum, the 'Grosse Pièce' offers a rare opportunity for collectors, with an estimated value ranging from $500,000 to $1,000,000.

The watch's creation narrative unfolds from 1914 when London-based S. Smith & Son commissioned Audemars Piguet for a celestial-themed timepiece through their London agents, Guignard & Golay. The Vallée de Joux, renowned as the "Valley of Complications," was the natural cradle for such an intricate project, with Audemars Piguet being among the elite few capable of undertaking it. The development spanned seven years, culminating in 1921. It involved a consortium of watchmaking luminaries, a practice known as établissage, where specialized producers contributed their expertise. Key figures included Charles Piguet for the base movement, Ami Meylan for jewelling, Marius Capt for spiraling, Henri Golay for the escapement and tourbillon integration (a feature not initially part of the ébauche), Louis-Élise Piguet's sons for chiming mechanisms, and Léon Aubert for the astronomical and perpetual calendar complications.

Aubert, celebrated for his work on similar English-commissioned, Swiss-made watches like the Dent 32'573, brought his unparalleled skill in astronomical mechanisms to the 'Grosse Pièce.' His previous innovations, including a unique mechanism for the equation of time complication sold to Patek Philippe, underscore his pivotal role in this project. The movement, numbered 16869, measures approximately 58.65mm, showcasing a ¾ plate in the English style, and features a Swiss lever escapement. In a pre-completion showcase at the Geneva Watch Exhibition in 1920, the watch, still undergoing refinements, demonstrated a sidereal time dial later replaced for enhanced legibility.

Upon its delivery to S. Smith & Sons in 1921, the dial was signed with "Trafalgar Square," and its 18k gold case, hallmarked FT for renowned English casemaker Frederick Thoms, incorporated sliders for striking modes and setting switches. The 'Grosse Pièce' then largely receded from public view until horological historian Gisbert Brunner's rediscovery in 1990, leading to its feature in his 1993 book on Audemars Piguet, co-authored with Christian Pfeiffer-Belli and Martin K. Wehrli. Robert Olmsted acquired the watch in March 1970 for $23,350 from Sydney Rosenberg, a sale meticulously documented with a wealth of paperwork, including a fitted wood box, an album of archival records, and AP's Extract from the Archives, cementing its irrefutable provenance.

In person, the 'Grosse Pièce' is a commanding presence, measuring 80mm in diameter, 34mm thick, and weighing 624 grams. Its double-sided design elegantly presents 19 complications, simplifying the display. The front features a white enamel dial with Roman numerals for standard time, complemented by four subdials indicating moon phases, power reserve, a combined chronograph counter, and month/leap-year cycle. A blued hand on the outer ring displays the equation of time. The reverse side, a captivating sky chart of the Northern Hemisphere viewed from London, showcases 315 gold-painted stars against a blue enamel backdrop, offering a unique blend of artistry and precision.

The movement's interior, as revealed by Audemars Piguet's detailed studies, highlights a full bridge supporting the tourbillon, designed with an English aesthetic in mind, despite retaining a Swiss lever escapement. The chiming complications are particularly noteworthy; their rich, round, and warm sound, facilitated by large gongs within the spacious case, has been lauded by experts. This auditory experience, coupled with its profound historical significance and robust provenance, distinguishes the 'Grosse Pièce' as a singular masterpiece among horological collectibles.

The reemergence of the 'Grosse Pièce' from Robert Olmsted's collection underscores the enduring allure of horological mastery and the captivating stories embedded within these intricate devices. Olmsted, a collector driven by pure passion rather than ego, meticulously lived with his timepieces, hand-winding them daily and obsessing over their accuracy. His collection, previously a private treasure, now offers a rare glimpse into a golden age of watchmaking. This auction is not just a sale; it's a testament to the timeless pursuit of precision and beauty, challenging us to reflect on the true value of artistry and dedication in an increasingly digital world. It serves as a potent reminder that some discoveries transcend generations, offering continuous fascination and a deeper appreciation for the marvels of human ingenuity.