ΔE 6.1, close: similar, with a visible difference side by side. Ink Dark Turquoise is warmer than Obsidian Pigment Toner. They are different kinds of paint: Army Painter Obsidian Pigment Toner is an opaque base/layer paint and Vallejo Ink Dark Turquoise is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 6). Ink Dark Turquoise is warmer than Obsidian Pigment Toner. They are different kinds of paint.
The same difference applies the other way round: Obsidian Pigment Toner is 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 Obsidian Pigment Toner on the colour wheel See Ink Dark Turquoise on the colour wheel
All matches: Obsidian Pigment Toner equivalents · Ink Dark Turquoise equivalents