Bright Gold vs Top Brass

How close are they?

ΔE 25.8, loose: different enough that you should pick on purpose. Top Brass is noticeably lighter, much more muted, warmer than Bright Gold.

Can I use Top Brass instead of Bright Gold?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 26). Top Brass is noticeably lighter, much more muted, warmer than Bright Gold.

Can I use Bright Gold instead of Top Brass?

The same difference applies the other way round: Bright Gold is noticeably darker, 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.