[Wil H]

Coal dust is quite explosive.

Did the Lusitania burn coal or anthracite?

Anthracite is comparatively dustless and burns hotter.

[fireforeffect]

Last time I checked, anthracite WAS coal.

Take a ton of anthracite coal, pile it up on top of a fused quarter stick of TNT. Detonate the TNT (while standing well back from the coal). Notice all the dust.

N.B.: This is why warships were being converted to fuel oil at this time.