Bright Gold vs Ancient Copper

How close are they?

ΔE 9.2, close: similar, with a visible difference side by side. Ancient Copper is warmer than Bright Gold.

Can I use Ancient Copper instead of Bright Gold?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Ancient Copper is warmer than Bright Gold.

Can I use Bright Gold instead of Ancient Copper?

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