Tharon stone
From Tardis Wiki, the free Doctor Who reference
The Tharon stone was a type of rock native to Tharos that was used by the native inhabitants there to help them manipulate the power of igneous rocks which the race had an affinity to, such as projecting energy and storing information. A group of Armidan came to Earth's Scotland with a Tharon Stone, but were attacked by the natives. The Stone was buried underground along with the statis capsules for the three surviving members of the group. (AUDIO: Vengeance of the Stones)
