Silver Chrome Nails
Silver chrome nails always make me think of the T-1000 terminator from Terminator 2: Judgment Day. And using chrome powder is easier than you think. This powder is color #10 (item #46283) from Born Pretty Store.
Apply a black base color.
Apply a layer of no-wipe gel top coat, and cure. You want the surface to be as smooth as possible because any imperfections are going to show with the chrome.