NEW YORK, June 7 (UPI) -- A set of five rare Patek Philippe titanium watches are set to go to auction Tuesday at Sotheby's, one of which is expected to fetch up to $1.5 million.
The highlight of the collection is the Patek Philippe Ref 5001T Sky Moon Tourbillon, the only known example of the watch in titanium. It could bring in $1 million to $1.5 million, Forbes reported.