ΔE 9.3, close: similar, with a visible difference side by side. Basilisk Green is a little darker, more muted, warmer than Turnbull Turquoise.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Basilisk Green is a little darker, more muted, warmer than Turnbull Turquoise.
The same difference applies the other way round: Turnbull Turquoise is a little lighter, more saturated, cooler.
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 Turnbull Turquoise on the colour wheel See Basilisk Green on the colour wheel
All matches: Turnbull Turquoise equivalents · Basilisk Green equivalents