ΔE 21.6, loose: different enough that you should pick on purpose. Iridescent Gold Deep (Fine) is noticeably lighter, more muted, warmer than Brass Scorpion. They are different kinds of paint: Citadel Brass Scorpion is a metallic and Golden Iridescent Gold Deep (Fine) is a pearl paint, so they won’t behave the same on the model even where the colour is close.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Iridescent Gold Deep (Fine) is noticeably lighter, more muted, warmer than Brass Scorpion. They are different kinds of paint.
The same difference applies the other way round: Brass Scorpion is noticeably darker, 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 Brass Scorpion on the colour wheel See Iridescent Gold Deep (Fine) on the colour wheel
All matches: Brass Scorpion equivalents · Iridescent Gold Deep (Fine) equivalents