These are the Sephora by OPI Trend Tips limited edition Betsey Johnson "Skulls." They are mainly silver and holographic while the skulls are a darker grayish green color.
I am not wearing any top coat here, which I must say turned out to be a major, major mistake. I have a little tip shrink because I've learned that most stickers do pull back a bit on me after they've set completely. Also, can I say that I wish the skulls faced down toward my tips?! The world should being seeing my skulls, not me. :)