In the 60's all DE blades were blued steel, then Wilkinson came along.
In 1970 I rolled my cigarettes with a V-Master machine, that used a l o n g cigarette paper and 6 DE blades to cut them into normal length. The V-Master allowed us to reverse the blades and flip them over; we had 4 cutting areas on each blade. I remember that Stainless Steel blades did not last very long, so I always bought Gillette Blue blades; they lasted 2 to 3 times longer.
Do they still make blue blades?