This stone might hold some great power. It appears that some ward protects it from identification. What a mystery!
History
During the autopsy of Kradva Ospen, the stone was found somewhere where the sun doesn't shine. Eitryll Windseeker handed the stone over to the Peas, and Grognock began to investigate it.
Leadbelly Fargus became very interested in the secrets of the stone and he tackled Grognock, winning a bout of strength in order to gain possession of the stone.
Leadbelly and Grognock were discussing the stone while Wander was eavesdropping, and he became interested in it as well. Believing the magic on the stone could be dispelled, he attempted to coerce Phaelnah into casting Dispel Magic on the stone, but she remained disinterested.
Phaelnah eventually cast Dispel Magic on the stone after some constant pestering from Wander, but it appeared to have no effect. Wander later investigated the stone and found himself no longer interested in it, but Leadbelly still brings up the stone and studies it from time to time. The current consensus is that the stone contains a complex mechanism inside that obscures something of great value.