Magister Nell:
Thank you! Go to the Forgotten Temple with your colleagues. Slay the roxide, the lakin undine, and the rowin undine to obtain Freezing Shards. Slay the death fire, the lakin salamander, and the salamander rowin to obtain Flare Shards.
I'd like to give you at least 5 restored Spirit Ores, so please bring me 200 fragments of each kind. You will be well rewarded.