ΔE 19.5, loose: different enough that you should pick on purpose. Ink Dark Turquoise is noticeably lighter, much more saturated than Black Ink.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Ink Dark Turquoise is noticeably lighter, much more saturated than Black Ink.
The same difference applies the other way round: Black Ink is noticeably darker, much 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 Black Ink on the colour wheel See Ink Dark Turquoise on the colour wheel
All matches: Black Ink equivalents · Ink Dark Turquoise equivalents