Thanks Pat and Erik,
Erik, I don't do any chemical silvering. Simply because I haven't gotten around to leaning it properly or getting set up with the bath/wet area/chemicals/ etc.
There is a company not far away that specializes in mirrors, they do hand-bevelling and silvering, so I just take it to them if I want chemical work. (it can stink up their place instead of mine...hahaha)
I would be wary of getting chemical silvering behind these types of thin glazes. The ammonia and hot water is pretty harsh and tends to eat the oil-based paints like gold size.
Any time I get silvering, I back up the decorative work with asphaltum, or I do the design work using epoxy inks. That way is survives. But of course, that's not going to be useful to get this type of effect.
Using the angel gilding kits seems to be a bit more gentle, but I don't have hand-on experience with it, so I don't know it's limits.
There's another example of this mica powder glaze technique on my website at
http://www.goldreverre.com/finishes.php....go to the two bottom left thumbnail in the left panel.