Broodmother Purple vs Blue Black

How close are they?

ΔE 19.0, loose: different enough that you should pick on purpose. Blue Black is a little lighter, much more muted, cooler than Broodmother Purple.

Can I use Blue Black instead of Broodmother Purple?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Blue Black is a little lighter, much more muted, cooler than Broodmother Purple.

Can I use Broodmother Purple instead of Blue Black?

The same difference applies the other way round: Broodmother Purple is a little darker, much more saturated, warmer.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.