ΔE 10.2, fair: the same colour family, but not a straight swap. Copper is a little darker, more muted than Ground Is Lava.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Copper is a little darker, more muted than Ground Is Lava.
The same difference applies the other way round: Ground Is Lava 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.
See Ground Is Lava on the colour wheel See Copper on the colour wheel
All matches: Ground Is Lava equivalents · Copper equivalents