A search for phosphor body color led to
http://www.espi-metals.com/technicaldata.htm#P
If you scroll down to P for phosphor, they list a number of color TV and other phosphors and state the body color. None of the color TV phosphors appear to be highly colored. However, there is a reference to a cadmium containing phosphor that is colored.
This leads me to think that the green-face tube were indeed the all-sulfide tubes, with cadmium used in at least the green phsophor.
Can someone with a green-faced tube do some investigation with a strong magnifier/microscope?
1) - Tube off - Are all 3 phosphors the same body color?
2) - Tube on, if the three phosphors are different with tube off - which emission color has which body color?