Sky Grey vs Gargoyle Grey

How close are they?

ΔE 7.4, close: similar, with a visible difference side by side. Gargoyle Grey is more saturated than Sky Grey.

Can I use Gargoyle Grey instead of Sky Grey?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Gargoyle Grey is more saturated than Sky Grey.

Can I use Sky Grey instead of Gargoyle Grey?

The same difference applies the other way round: Sky Grey is 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.