Weber officially stopped selling the dark blue kettles in the U.S. after the 2013 (AT) model year. However, some European countries still have access to this color as well as a few others.
The earliest blue kettles were a more of a turquois/aqua finish then switching in the early 1960s to a more baby blue finish before being discontinued at the end of 1966. Weber would bring back the color in the form of Dark Blue during the 1978 model year and was available with minor variation in pigment/dye lot in the U.S. through 2013.
I have a dark blue first gen. gas grill. When did they stop making the round gas grills?