ΔE 11.7, fair: the same colour family, but not a straight swap. New Gold is a little lighter, warmer than Runelord Brass.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). New Gold is a little lighter, warmer than Runelord Brass.
The same difference applies the other way round: Runelord Brass is a little darker, 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.
See Runelord Brass on the colour wheel See New Gold on the colour wheel
All matches: Runelord Brass equivalents · New Gold equivalents