T'au Light Ochre vs Cokum Copper

How close are they?

ΔE 11.5, fair: the same colour family, but not a straight swap. Cokum Copper is a little darker, more muted than T'au Light Ochre.

Can I use Cokum Copper instead of T'au Light Ochre?

Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Cokum Copper is a little darker, more muted than T'au Light Ochre.

Can I use T'au Light Ochre instead of Cokum Copper?

The same difference applies the other way round: T'au Light Ochre 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.