Frostheart vs Celestial Blue

How close are they?

ΔE 9.3, close: similar, with a visible difference side by side. Celestial Blue is a little lighter, more muted than Frostheart. They are different kinds of paint: Citadel Frostheart is a one-coat contrast-style paint and Two Thin Coats Celestial Blue is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.

Can I use Celestial Blue instead of Frostheart?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Celestial Blue is a little lighter, more muted than Frostheart. They are different kinds of paint.

Can I use Frostheart instead of Celestial Blue?

The same difference applies the other way round: Frostheart is a little darker, more saturated.

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.