ΔE 16.4, loose: different enough that you should pick on purpose. Imperial Gold is a little lighter, much more muted than Bright Gold.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Imperial Gold is a little lighter, much more muted than Bright Gold.
The same difference applies the other way round: Bright Gold is a little darker, much 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 Bright Gold on the colour wheel See Imperial Gold on the colour wheel
All matches: Bright Gold equivalents · Imperial Gold equivalents