Copper vs Red Copper

How close are they?

ΔE 14.4, fair: the same colour family, but not a straight swap. Red Copper is a little darker, more muted than Copper.

Can I use Red Copper instead of Copper?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Red Copper is a little darker, more muted than Copper.

Can I use Copper instead of Red Copper?

The same difference applies the other way round: Copper is a little lighter, more saturated.

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.