ΔE 23.1, loose: different enough that you should pick on purpose. Pure Filth is noticeably darker, much more muted, warmer than Barren Dune.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Pure Filth is noticeably darker, much more muted, warmer than Barren Dune.
The same difference applies the other way round: Barren Dune is noticeably lighter, much more saturated, cooler.
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 Barren Dune on the colour wheel See Pure Filth on the colour wheel
All matches: Barren Dune equivalents · Pure Filth equivalents