ΔE 12.0, fair: the same colour family, but not a straight swap. Tarnished Brass is noticeably darker than Greedy Gold.
Can I use Tarnished Brass instead of Greedy Gold?
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Tarnished Brass is noticeably darker than Greedy Gold.
Can I use Greedy Gold instead of Tarnished Brass?
The same difference applies the other way round: Greedy Gold is noticeably lighter.
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.