Iridescent Bronze (Fine) vs Arcane Gold

How close are they?

ΔE 23.2, loose: different enough that you should pick on purpose. Arcane Gold is noticeably darker, more saturated, warmer than Iridescent Bronze (Fine). They are different kinds of paint: Golden Iridescent Bronze (Fine) is a pearl paint and Vallejo Arcane Gold is a metallic, so they won’t behave the same on the model even where the colour is close.

Can I use Arcane Gold instead of Iridescent Bronze (Fine)?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 23). Arcane Gold is noticeably darker, more saturated, warmer than Iridescent Bronze (Fine). They are different kinds of paint.

Can I use Iridescent Bronze (Fine) instead of Arcane Gold?

The same difference applies the other way round: Iridescent Bronze (Fine) is noticeably lighter, 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.