I used only 3 polishes: white is Pure Ice - Superstar! Finger Paints - Pop Art Purple and Jessica Phenom - Blue Blooded. This looks like reciprocal gradient or just double gradient - lines are blurry with me to know which one to pick.
I added some studs ( I'm on the stud kick lately). Triangular one on the ring and middle finger reminds me of little space ship landing or taking of into a purple mist...