ΔE 11.8, fair: the same colour family, but not a straight swap. Chromium Oxide Green is more muted than Biel-Tan Green. They are different kinds of paint: Citadel Biel-Tan Green is a wash/shade and Golden Chromium Oxide Green is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Chromium Oxide Green is more muted than Biel-Tan Green. They are different kinds of paint.
The same difference applies the other way round: Biel-Tan Green is more saturated.
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 Biel-Tan Green on the colour wheel See Chromium Oxide Green on the colour wheel
All matches: Biel-Tan Green equivalents · Chromium Oxide Green equivalents