ΔE 14.8, fair: the same colour family, but not a straight swap. Celestial Blue is much more muted, warmer than Arctic Gem.
✓ Two Thin Coats comparison chart lists these two as equivalents.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Celestial Blue is much more muted, warmer than Arctic Gem.
The same difference applies the other way round: Arctic Gem is much 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 Arctic Gem on the colour wheel See Celestial Blue on the colour wheel
All matches: Arctic Gem equivalents · Celestial Blue equivalents