ΔE 21.1, loose: different enough that you should pick on purpose. Verdigris is noticeably lighter, more saturated than Ivory Tusk.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Verdigris is noticeably lighter, more saturated than Ivory Tusk.
The same difference applies the other way round: Ivory Tusk is noticeably darker, more muted.
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 Ivory Tusk on the colour wheel See Verdigris on the colour wheel
All matches: Ivory Tusk equivalents · Verdigris equivalents