ΔE 8.8, close: similar, with a visible difference side by side. Rich Gold is a little lighter, more saturated, warmer than Retributor Armour.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Rich Gold is a little lighter, more saturated, warmer than Retributor Armour.
The same difference applies the other way round: Retributor Armour is a little darker, more muted, 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 Retributor Armour on the colour wheel See Rich Gold on the colour wheel
All matches: Retributor Armour equivalents · Rich Gold equivalents