Acanthus is right it's not going anywhere. The pedestal isn't brick and mortar, it's literally embedded in the ground. There is no way of removing it with out destroying it further. She does, however, spot a shard of the glassy material on the ground as she tried to move the extant remains of the mirror. The same magical runes are on the inside, with the very faintest flicker of magic emanating from them, and she now notices that the non-magical rune on the mirror's pedestal is repeated multiple times amongst other words upon the outer rim.