Though I call it a G as well, when I posted this chip here a few years ago asking if this was a G, I was told by David Spragg the monogram is GC... To my eyes the first letter is a G as in General Mills and the second letter is also a G. The casino is Grand Cercle Aix-les-Bains, and came.straight from the casino into my hands in 1992
There are several French monograms with a C that look like a G.