I' probably wrong about this...
....but I seem to recall reading somewhere that
explosive-filled artillery shells have a yellow-band to identify them;
and chemical-filled artillery shells have a blue-band for identification.
I could be wrong. It's worthwhile to check up on this [either
some textbook, or internet site].
Regardless! What should worry you is that Al Qaeda knows
what artillery-shells contain what.
I am NOW 99% convinced that Al Qaeda now has both radiological material & chemical-agents [nerve-agents, cyanide, mustard] in LARGE enough quantities [kilos, or tens of kilos]
to kill 'thousands'.