ΔE 13.1, fair: the same colour family, but not a straight swap. Ivory Tusk is noticeably darker, more muted than Bleached Bone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Ivory Tusk is noticeably darker, more muted than Bleached Bone.
The same difference applies the other way round: Bleached Bone is noticeably 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.
See Bleached Bone on the colour wheel See Ivory Tusk on the colour wheel
All matches: Bleached Bone equivalents · Ivory Tusk equivalents