ΔE 7.1, close: similar, with a visible difference side by side. Basilicanum Grey is a little lighter, more muted than Gravelord Grey.
✓ Herrick Games paint comparison chart lists these two as equivalents.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Basilicanum Grey is a little lighter, more muted than Gravelord Grey.
The same difference applies the other way round: Gravelord Grey is a little darker, 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 Gravelord Grey on the colour wheel See Basilicanum Grey on the colour wheel
All matches: Gravelord Grey equivalents · Basilicanum Grey equivalents