i'm no expert but i did like french at school and with Mavic being french it always interested me what the letters stood for. i think this is what i concluded back in 1996!
CD = Couche Dure, dark grey/brown, hard cooked, stronger than standard SUP
SUP = Soude Udine Process or something, silver rim, standard rim manufacture
TIB = same as SUP but with a goldish finish, can't remember what TIB stands for though!
Sunset = not dissimilar to TIB but more of a bronzey finish i think
Citron = lemon yellowy, these came a bit later on i think
Ceramic = coating on brake surface, a lot of people on ebay describe CD rims as ceramics!
does this help?