More than S$20.6 million (CHF15 million). That’s how much the Henry Graves Supercomplication by Patek Philippe is expected to fetch when it goes under the Sotheby’s hammer (not literally, of course) in Geneva on November 11. Completed by the Swiss manufacture in 1933 for American banker Henry Graves, the pocket watch’s claim to fame, aside from its staggering estimated price tag, is that it was (and remains) the world’s most complicated timepiece made entirely by hand.
This will be the second time this watch is going on the block. In 1999, the Henry Graves Supercomplication was sold by Sotheby’s for a record-breaking US$11 million (S$13.7 million) to an anonymous bidder. The identity of this mysterious buyer, however, did not stay secret for long: Three years later, it was reported that a member of the Qatari royal family owed Sotheby’s US$83 million, and had pledged several of his collectibles to the auction house to pay off this debt. The Henry Graves Supercomplication was one of those items. Here’s what makes this timepiece tick.

1) High function: A total of 24 complications makes this the most complicated watch wholly made by hand. It was the world’s most complex timepiece for 56 years, until Patek Philippe broke its own record in 1989 with the 33-complication Calibre 89, created with the help of computer-assisted engineering.
2) Top of the charts: Aside from a chart of the night sky over New York City, this watch’s additional functions include a perpetual calendar, moon phases, sidereal time, a chronograph, sunset/sunrise indications, a power reserve indicator and a Westminster minute repeater.
3) Worth its weight: Clocking in at 539 grams and comprising more than 900 components, this 18-karat gold watch took three years to research and five years to produce.
4) Happy birthday: The auction of what is arguably the world’s most famous timepiece coincides with Patek Philippe’s 175th anniversary celebrations. By the way, Henry Graves paid the manufacture CHF60,000 for the watch eight decades ago.