Gene,
Like this one:

http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=489300&page=all

There are lots of photos of this Halifax in the post, and I'm too lazy to break them out. The early French bone pack colors are muted, with more faint blues than, say, St. Ledger colors.

Later Darnes, post WWII have cyanide case colors, with or without a lacquer over the top. I've seen the lacquer thick enough that when it chipped off, it took the colors with it, giving the odd appearance of chipped off case colors.

Keep in mind that the French grey you see on higher grade Darne and other French guns, is an actual hardening process, with the quench happening in a solution of potassium prusiate, instead of tap water. The chemistry of the quench can be played with to give color from pewter to almost a silver plated look. I'd say it is no more or less durable than color case hardening. But, it is a hardening process, and not simply a silver color.

Best,
Ted