ΔE 9.3, close: similar, with a visible difference side by side. Ground Is Lava is a little lighter, more muted than Gemstone Red.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Ground Is Lava is a little lighter, more muted than Gemstone Red.
The same difference applies the other way round: Gemstone Red 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 Gemstone Red on the colour wheel See Ground Is Lava on the colour wheel
All matches: Gemstone Red equivalents · Ground Is Lava equivalents