Speak with Jern Hornhelm in Thelsamar.
If Ironband still needs blastpowder, then by Magni he'll have it! I sent the approval on ahead with a messenger to Jern Hornhelm in Thelsamar. He'll prepare the powder and other supplies to take to Ironband.
And one more thing: I want you to personally see that the shipment of powder reaches its destination. The last one didn't, so keep your mind sharp and your eyes open.