Blue Black vs Dk Mediterr. Blue

How close are they?

ΔE 6.9, close: similar, with a visible difference side by side. Dk Mediterr. Blue is a little lighter, more saturated than Blue Black.

Can I use Dk Mediterr. Blue instead of Blue Black?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Dk Mediterr. Blue is a little lighter, more saturated than Blue Black.

Can I use Blue Black instead of Dk Mediterr. Blue?

The same difference applies the other way round: Blue Black is a little darker, more muted.

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.