ΔE 17.9, loose: different enough that you should pick on purpose. Imperial Gold is a little lighter, more muted, warmer than Antique Gold.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Imperial Gold is a little lighter, more muted, warmer than Antique Gold.
The same difference applies the other way round: Antique Gold is a little 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 Antique Gold on the colour wheel See Imperial Gold on the colour wheel
All matches: Antique Gold equivalents · Imperial Gold equivalents