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Hands-On With The Rolex Sea-Dweller Ref. 16660

The history of the Sea-Dweller has quite a lot of depth, and includes some rare pearls such as the Sea-Dweller Ref. 16660, explains Giorgia Mondani...

Hands-On With The Rolex Sea-Dweller Ref. 16660
Hands-On With The Rolex Sea-Dweller Ref. 16660  |  Photo: Haute Time / brand
The Short Answer

The history of the Sea-Dweller has quite a lot of depth, and includes some rare pearls such as the Sea-Dweller Ref. 16660, explains Giorgia Mondani...

“Guido Mondani Editore” is a publishing house founded by Guido Mondani in 1979, specialized in haute horlogerie, that has become a reference for dealers and collectors all over the world. Today, Giorgia Mondani perpetuates her father’s passion, revealing the secrets behind the most prized vintage watches, and hoping to guide our readers towards their dream purchase.

Giorgia Mondani
Giorgia (left) and Guido Mondani (right)

Remember when James Cameron reached the ocean’s deepest point, on March, 26, 2012? He famously wore an Oyster Perpetual Rolex Deepsea Challenge on the wrist. But other Rolex watches have achieved legendary status via underwater explorations, including the Rolex Sea-Dweller.

Rolex Sea-Dweller Ref. 16660 Mark III
Rolex Sea-Dweller Ref. 16660 Mark III

The history of the Sea-Dweller has quite a lot of depth, and includes some rare pearls such as the Sea-Dweller Ref. 16660, aka the “triple six.” Rolex introduced Ref. 16660 in 1978 as the ‘evolution’ of Ref. 6565, and increased the tested depth rating from 610 to 1220 meters, thus doubling the surface of exploration.

Rolex Sea-Dweller Ref. 16660 Mark III
Rolex Sea-Dweller Ref. 16660 Mark III

Produced between 1978 and 1988, it is recognizable because of its sapphire crystal, unidirectional rotating bezel, larger and more reliable helium escape valve, as well as its new caliber 3035. During its brief, ten-year existence, Ref. 16660 underwent several changes, Mark I and Mark II featuring dials with “circular” indexes, while Mark III, Mark IV, and Mark V featured “circular edge indexes” (indexes surrounded by a ring, mostly in white gold).

Rolex Sea-Dweller Ref. 16660 Mark III
Rolex Sea-Dweller Ref. 16660 Mark III

However, Rolex enthusiasts enjoy dwelling most on the even more intricate changes between each model, including the overlapping “f” in “4000ft” of the Mark I, adjusted in the second iteration, or the slightly misplaced hyphen in “Swiss-T<25” in Mark III, later corrected in Mark IV and deleted altogether in Mark V.

Rolex Sea-Dweller Ref. 16660 Mark III
Rolex Sea-Dweller Ref. 16660 Mark III

To learn more about the Rolex Sea-Dweller Ref. 16660, and find out the differences between Mark I,II,III,IV and V, please refer to “Collecting Rolex Submariner” a fantastic book which dedicates a huge chapter to every Sea-Dweller produced.

Photo Credit: Giorgia Mondani.For more information about theSea-Dweller Ref. 16660, please visit Collecting Watches

Adrienne Faurote
Adrienne Faurote
Haute Time
As a former New Yorker, now a “Miamian,” Adrienne Faurote joined Haute Living in August of 2021. She currently serves as the Haute Media Group Editor-in-Chief, overseeing all editorial platforms within the Haute Media Group while also maintaining her role as Fashion, Jewelry & Watch Director. Prior to her position at Haute Living, Faurote was the Market Editor at Marie Claire Magazine US, amassing over ten years in the industry, becoming an authoritative voice in all things fashion, jewelry, and watches.
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