Basilisk Brown vs Middle Stone

How close are they?

ΔE 6.4, close: similar, with a visible difference side by side. Middle Stone is more saturated than Basilisk Brown.

Can I use Middle Stone instead of Basilisk Brown?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Middle Stone is more saturated than Basilisk Brown.

Can I use Basilisk Brown instead of Middle Stone?

The same difference applies the other way round: Basilisk Brown 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.