Grim Rust vs Raw Sienna

How close are they?

ΔE 9.4, close: similar, with a visible difference side by side. Raw Sienna is a little lighter, more muted than Grim Rust. They are different kinds of paint: Army Painter Grim Rust is a fluorescent or effect paint and Golden Raw Sienna is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.

Can I use Raw Sienna instead of Grim Rust?

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

Can I use Grim Rust instead of Raw Sienna?

The same difference applies the other way round: Grim Rust 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.