I got the Dior Rock Coat a few months ago at Nordstorm but didn't get to play with it until now. It is a sheer black jelly base that comes in a 10ml bottle and is supposed to give an ombre look when applied over a color. I like it but think that you can franken your own easily and cheaper with a couple drops of black polish in a clear base. According to Dior, Rock Coat is "the ultimate smoky topcoat. As a topcoat, its semi-transparent black formula coats varnish with a veil of smoky lacquer, extending wear and increasing shine. Your nail varnish takes on an enigmatic 'rock' look." Well let's see. I layered it over different colors.
All pictures were taken in an artificial light setting without flash.
-One coat of Rock Coat over two coats of Essie Playa Del Platinum, no top coat