Blue Black is a dark, navy blue with a black base and lighter, brighter blue pearl. The color payoff was good--just shy of full coverage--and applied evenly to the lid. I felt like this shade looked more satin by the time I blended it out, as the shimmer did not seem as present or as reflective. It wore well for eight hours on me before fading.
FURTHER READING: Formula Overview, which is a detailed review of the range as a whole.