It seems to be two different fonts.

The SG - and that could be something like Italiana

and the imon something else... I'm starting to think a regular Italic font - and not a script... Sorry I can't be more helpful. Hopefully someone will ID it...

http://www.dafont.com/forum/read/61871/cartier-font

Maybe it was the font used here...

On another site, one of the mods suggested modifying Didot Italic - but it isn't it either... but it can help give you something similar.