Light Bronze vs Gold Brown

How close are they?

ΔE 18.5, loose: different enough that you should pick on purpose. Gold Brown is a little darker, much more saturated, warmer than Light Bronze.

Can I use Gold Brown instead of Light Bronze?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Gold Brown is a little darker, much more saturated, warmer than Light Bronze.

Can I use Light Bronze instead of Gold Brown?

The same difference applies the other way round: Light Bronze is a little lighter, much more muted, 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.