Piggy Purple Ink vs Ink Blue

How close are they?

ΔE 18.4, loose: different enough that you should pick on purpose. Ink Blue is noticeably darker, cooler than Piggy Purple Ink.

Can I use Ink Blue instead of Piggy Purple Ink?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Ink Blue is noticeably darker, cooler than Piggy Purple Ink.

Can I use Piggy Purple Ink instead of Ink Blue?

The same difference applies the other way round: Piggy Purple Ink is noticeably lighter, warmer.

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.