ΔE 17.7, loose: different enough that you should pick on purpose. Necro Gold is a little darker, much more saturated than Steel.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Necro Gold is a little darker, much more saturated than Steel.
The same difference applies the other way round: Steel is a little lighter, much 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 Steel on the colour wheel See Necro Gold on the colour wheel
All matches: Steel equivalents · Necro Gold equivalents