ΔE 6.4, close: similar, with a visible difference side by side. Raw Umber is more muted than Stirland Mud. They are different kinds of paint: Citadel Stirland Mud is a technical paint or medium and Scale75 Raw Umber is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Raw Umber is more muted than Stirland Mud. They are different kinds of paint.
The same difference applies the other way round: Stirland Mud is 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.
See Stirland Mud on the colour wheel See Raw Umber on the colour wheel
All matches: Stirland Mud equivalents · Raw Umber equivalents