Metallic Rose vs Pure Copper

How close are they?

ΔE 9.3, close: similar, with a visible difference side by side. Pure Copper is a little darker, warmer than Metallic Rose.

Can I use Pure Copper instead of Metallic Rose?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Pure Copper is a little darker, warmer than Metallic Rose.

Can I use Metallic Rose instead of Pure Copper?

The same difference applies the other way round: Metallic Rose is a little lighter, 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.