Green Stone vs Landser Grey

How close are they?

ΔE 6.1, close: similar, with a visible difference side by side. Landser Grey is a little darker than Green Stone.

Can I use Landser Grey instead of Green Stone?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Landser Grey is a little darker than Green Stone.

Can I use Green Stone instead of Landser Grey?

The same difference applies the other way round: Green Stone is a little lighter.

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.