*sigh* posting this is making me want old school and old old school UD polish even more. although they did re-release Big Bang in the Apocalyptic set (the same set Gunmetal came from), so maybe they'll do another re-release when they come out with Book of Shadows III. i'm really hoping for Salmonella or Live Wire, but i'd be happy with anything.
Gunmetal is a shimmery charcoal that has some blue in it as well. in some lights it also takes on a brown cast. i used two coats here, if i remember correctly it applied a bit streaky but was fine after the top coat.