Can someone describe to me the color of a /C mercury vapor lamp?
A description of the color of a /R, /W and /N would also be nice. 

I've heard that /C have a slightly lime greenish color, like the one below but not that strong.

I've heard that /C have a slightly lime greenish color, like the one below but not that strong.

Similar to a verd-a-lite/warm green fluorescent?

Similar to a verd-a-lite/warm green fluorescent?

I don't know, but check that post where we discussed about green lights.