Silver Grey vs Bony Spikes

How close are they?

ΔE 6.1, close: similar, with a visible difference side by side. Bony Spikes is a little lighter, warmer than Silver Grey.

Can I use Bony Spikes instead of Silver Grey?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Bony Spikes is a little lighter, warmer than Silver Grey.

Can I use Silver Grey instead of Bony Spikes?

The same difference applies the other way round: Silver Grey is a little darker, cooler.

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.