An elusive Rolex triple calendar with moonphase in 18K yellow gold, which belong to the last emperor of Vietnam, is on the auction block again next month. Widely expected to create a new record, the watch was owned by Emperor Bao Dai and is up for grabs at auction house Philips’s Geneva auction on May 13-14 this year.

One of three 6062 dials in black.

Considered one of the most valuable Rolexes ever made, this timepiece is only one of three Ref. 6062 produced with a black dial. Further more, of the three black dials, only the Bao Dai-owned 6062 has diamond markers, making it a truly collectible and unique Rolex.

So not only this Rolex a rare and iconic model but it also has imperial provenance, having belonged to the last emperor of Vietnam. No surprise that it has a pre-sale estimate of $1.5 million.

A Rolex with a moonphase is rare.Born Nguyen Phúc Vĩnh Thụy, Bao Dai was the 13th and last emperor of the Nguyen Dynasty. At the age 12 in 1926, he ascended the throne and was granted the title of Bao Dai – Keeper of Greatness. He ruled for close to 30 years before abdicating the throne in 1955. He died in exile in Paris in 1997.

It is believed that Bao Dai, who lived a life of high style (he also owned a custom-bodied Ferrari 375 MM Spyder), purchased the watch himself in Geneva in 1954. He did so whilst attending the historic Geneva Conference seeking peace in Indochina following the Korean War.

A report on WatchesbySJX says the watch is believed to have cost CHF 4,000 then, almost the same as a Patek Philippe perpetual calendar.

The Ref. 6062 is the most complicated and iconic Oyster-cased model created by Rolex. It features day, date, month and moonphase indications. Incidentally, Rolex never produced a moonphase after the Ref. 6062 till it unveiled a new Cellini Moonphase at Baselworld this year.

A file pic of the this Ref. 6062.

Incidentally, the “Bao Dai Rolex” first appeared on the market in 2002, when Phillips sold it for a then record-breaking price, making it the most expensive Rolex ever sold (CHF 370,000) at an auction. According to Aurel Bacs, Senior Consultant at Philips, the Bao Dai Rolex is a “mythical watch that occupies the dreams of scholars, collectors, and enthusiasts all over the world.”

It comes to the auction now from a private collector. Incidentally, this is the second time this Rolex has turned up with the famed auctioneer. He previously acquired it for sale from the late emperor’s son.

The most expensive Rolex sold at an auction this far is the Ref. 4113 split-seconds chronograph that fetched $2.5 million at a Philips auction in May 2016.