Ushabti Bone vs Trollblood Highlight

How close are they?

ΔE 15.0, loose: different enough that you should pick on purpose. Trollblood Highlight is a little darker, much more muted than Ushabti Bone.

Can I use Trollblood Highlight instead of Ushabti Bone?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Trollblood Highlight is a little darker, much more muted than Ushabti Bone.

Can I use Ushabti Bone instead of Trollblood Highlight?

The same difference applies the other way round: Ushabti Bone is a little lighter, much 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.