My 1973 Mercier was light blue, with black, gold and white trim. Only the head tube badge was a foil transfer. The down tube and seat tube logos were painted in a multi-step process that was finished with a sort of air brush fade, if that makes any sense at all.
I recently saw photos that I had taken of the frame back in ~1983 or so. Using a 35mm film camera. I'll need to scan or image the prints to post them. PG