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And then, near the end of the Phillips catalog, there's a very attractive 2998-1 with a tropical dial that is not necessarily extraordinary outside of its great condition, but it's hard not rolex tiffany dial to draw parallels to the unexpected success of the tropical-dial link 2915-1 from this time last year. Outside of Phillips, Sotheby's has a first-series 2915 that could help serve as a bellwether of interest in early Speedmasters at the very link top end of the collector pool.

Across both references there are four known dial types categorized as Mark 1 Mark 1.5 Mark 1.75 and Mark 2. This odd nomenclature happens a lot with link vintage Rolex I would imagine at some point there were only two dial variants link and then someone found a slight difference creating Mark 1.5 in the middle. By the same process the Mark 1.75 was "discovered" later down the link collecting line.