Mitre crystals are like stalactites on the caves, varying in size, but they can't be mined with the usual tools. It was very easy to damage, and the one's collecting must do with precision using a pickaxe, but being very careful during the process.
The Witch has not lied about the mine here, but the natural cave was too small. If there are more mitre crystals on the mountain, it would be impossible to extract everything. They would have to expand the cave using pickaxes while being careful, a prolonged process and in the natural cave were just a few crystals.
Usually, in the mines are used non-humans, slaves, they work till death without rest, but this was already too much. Mining mitre was far different from the other minerals. The delicate process of extracting it from the caves alone was challenging, so Gremory wondered how he would use this mine.
