Terrible news adventurer. The caravan bringing the other materials I needed was attacked by giant spiders shortly after entering the pass.
Among the items they were carrying would have been a pouch of grey celestium dust. You might be familiar with celestium. This type is special, and I use it to make the infusion to inscribe the glyphs.
Unfortunately there is no easy way to get more. I hate to ask, but could you go after those spiders and recover the dust shipment? Once I have it, I can create more powerful glyphs to aid you and your fellows.