High Priest Sylvain:
Ah, the Crystal of Purity! Behold the beauty of the most pure formation!
To tell you the truth, I knew that Maria wasn't quite ready to make the crystal and I thought that you might help her find the way.
Thanks to you, the method of creating this crystal has been restored to us, and we have the object we need to purify the Execution Grounds. Good work.
You shall have the mark as promised. Take it to Magister Mirien over there. Good luck in the Trial of the Scholar.