Sephora Formula X Mastermind
Recently, I went to TJ Maxx in search of polish gems, and I found a 2 full-sized bottles of Sephora Formula X packaged together for just $4.50. The pack contained Mastermind, swatches above, and a holo topcoat called Oh! Zone. (You can never have too many holo topcoats! #amiright)
A Google search didn't tell me much about Mastermind, but it appears it was part of the New Classics collection, described as "lavender pearl", and is no longer available. To me, lavender is usually used to describe lighter shades, so it just doesn't suit this shade. It's more of a plum to me. It's really quite pretty and it you enlarge the pic, you'll see flashes of red in there that make it shine in the sun.