Aquamarine vs Aqua Alchemy

How close are they?

ΔE 10.0, close: similar, with a visible difference side by side. Aqua Alchemy is a little darker, more saturated, warmer than Aquamarine.

Can I use Aqua Alchemy instead of Aquamarine?

Usually, if you are not matching paint already on the model. Close match (ΔE 10). Aqua Alchemy is a little darker, more saturated, warmer than Aquamarine.

Can I use Aquamarine instead of Aqua Alchemy?

The same difference applies the other way round: Aquamarine is a little lighter, more muted, 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.