Greedy Gold vs Copper Coin

How close are they?

ΔE 20.5, loose: different enough that you should pick on purpose. Copper Coin is noticeably darker, warmer than Greedy Gold.

Can I use Copper Coin instead of Greedy Gold?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Copper Coin is noticeably darker, warmer than Greedy Gold.

Can I use Greedy Gold instead of Copper Coin?

The same difference applies the other way round: Greedy Gold is noticeably lighter, 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.