Hydra Turquoise vs Adriatic Blue

How close are they?

ΔE 9.6, close: similar, with a visible difference side by side. Adriatic Blue is a little lighter, more saturated than Hydra Turquoise.

Can I use Adriatic Blue instead of Hydra Turquoise?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Adriatic Blue is a little lighter, more saturated than Hydra Turquoise.

Can I use Hydra Turquoise instead of Adriatic Blue?

The same difference applies the other way round: Hydra Turquoise is a little darker, 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.