ΔE 12.9, fair: the same colour family, but not a straight swap. Mahogany is a little darker, more saturated than Green Stone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Mahogany is a little darker, more saturated than Green Stone.
The same difference applies the other way round: Green Stone is a little lighter, 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.
See Green Stone on the colour wheel See Mahogany on the colour wheel
All matches: Green Stone equivalents · Mahogany equivalents