Rolexes in general are pretty much all the same and models last decades in their catalog. The big difference in most models is all about the dial. This 16013 is of their first year of production and is insanely rare because of the said dial. The gilding of a dial is a reverse pain process where the brass plate shows through the painted dial. The dial goes from a near black to a very electric blue depending on the light, it is very impressive to see in person. The watch has been slightly polished previously but remains very thick overall. Caseback is unpolished and bears the mark: GO FOR IT! That says it all.
 
Details:
 
Brand: Rolex
Model: Datejust
Reference: 16013
Year: 1979
Material: Stainless Steel and 18k Gold
Dimensions:  36mm
Crystal:  Plexiglass
Movement: Automatic Cal 3035
Bracelet/Strap: Wristwatchme Leather Band
Box/Papers: No/No