Ahriman Blue vs Cold Armour

How close are they?

ΔE 17.2, loose: different enough that you should pick on purpose. Cold Armour is much more muted, warmer than Ahriman Blue.

Can I use Cold Armour instead of Ahriman Blue?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Cold Armour is much more muted, warmer than Ahriman Blue.

Can I use Ahriman Blue instead of Cold Armour?

The same difference applies the other way round: Ahriman Blue is much more saturated, cooler.

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.