Artefact - Pierre Magique d'Erechtheus
This item is about two feet wide and a few inches thick. It is a lesser magic device enchanted with one constant effect that changes it and whatever person is carrying it into a rock of the same size as the base item (MuCoTe Base 25, +1 Touch, +2 Sun, +1 for special effect; +4 constant = Level 49). If its effect is dispelled, it will slip from hands, but whoever picks it up might be affected by it the next time it triggers. Since part of the stone’s effect is that it changes itself along with its wielder, the stone will remain part of the wielder if he is magically given another form, and will change him back into a rock as soon as the new spell wears off. Investigation in the lab reveals that there is a way to cancel the effect, which requires that the person make a particular sign with the fingers on either hand, and wiggle like a snake. These gestures cannot be seen by others, but the device knows when they have been performed.