Among the most collected artists in the world, Andy Warhol was himself a collector—and an avid one at that. Wristwatches, in particular, were among his obsession. The king of Pop art amassed over 300 of them, from Rolex and Cartier to Piaget and Patek Philippe, and it’s thought he never parted with his horological treasures.

Shortly after his death in 1988, all of his possessions were sold in a marathon Sotheby’s auction lasting 10 days and attracting thousands of would-be bidders. Many were turned away due to lack of space (no online bidding in those days). Lining three full floors of Sotheby’s New York, the lots numbered in the thousands and ranged from genuine art (Picasso, Magritte, Klee) to that of the knickknack variety—including, famously, 175 cookie jars. His friends called it “Andy’s stuff”, the New York Times called it “a gargantuan homage to consumerism.”

Those 300 Warhol timepieces went under the hammer, too, fanning out to their new owners around the world. But now one of them, among his most cherished, is returning to the auction block. On December 5, Warhol’s Patek Philippe Reference 3448 will go under the gavel at Christie’s Important Watches live auction in New York, where it’s estimated to bag $350,000–$600,000.

Reference 3448 was unveiled in 1962 and housed the first self-winding perpetual calendar movement—not just Patek’s first, but the world’s. Over time, the model was re-crafted with four dial variations. The piece belonging to Warhol, which he bought in 1978, was the last of those dials and is believed to be one of only 450 such watches ever made. 

The 18-karat gold watch features gold hands and hour markers, and a starry moon display at six o’clock. It had remained with its buyer for 35 years until, in 2014, it was acquired at Sotheby’s Geneva by the present owner.

The watch is in “superb overall condition, featuring an extremely attractive and well-preserved dial with perfectly clear markers and signatures,” says Christie’s, adding that the dial was “perfectly cleaned and restored by Patek Philippe in the mid-1980s” yet preserves the silky finish that has become a trademark of its designer, Stern Frères.

Another sensational watch in Christie’s sale is Richard Mille’s RM018 Hommage à Boucheron. The 18-karat white gold ‘skeletonized’ wristwatch was made in 2008 to commemorate the 150th anniversary of the French luxury jewelry house of Boucheron. One of only 30 made, it is estimated to fetch $500,000–$1 million.

The watches will be exhibited in Christie’s Rockefeller Center location from December 1–4 ahead of the December 5 live auction.