Burning Ore vs Dwarven Flesh

How close are they?

ΔE 16.2, loose: different enough that you should pick on purpose. Dwarven Flesh is a little lighter, much more muted than Burning Ore.

Can I use Dwarven Flesh instead of Burning Ore?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Dwarven Flesh is a little lighter, much more muted than Burning Ore.

Can I use Burning Ore instead of Dwarven Flesh?

The same difference applies the other way round: Burning Ore is a little darker, much 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.