Elder Filaur:
Please destroy the following monsters in the Mithril Mine: Grave Robber Summoners, Grave Robber Magicians, Grave Robber Workers, Grave Robber Warriors and Grave Robber Insane Warriors, since they seem to be the chief ones causing the trouble. While you're at it, destroy their subordinates: Servitors of Darkness, Phantoms of the Mine, Mine Bugs and Earthworm's Descendants.
Bring me enough Mineral Fragments as evidence and I will give you a reward: either a recipe or Premium Materials containing the secrets of Dwarven armor
What are you still doing standing there? Get moving!