M A Czaplicka - Pebble destruction
Type of Spiritual Experience
A description of the experience
Shamanism in Siberia - excerpts from Aboriginal Siberia by M. A. CZAPLICKA 
Upune, the wife of a dead Chukchee shaman, possessed wonderful shamanistic power; she herself declared that she had only a small part of her husband's ability. In a shamanistic performance 'she took a large round pebble of the size of a man's fist, set it upon the drum, and, blowing upon it from all sides, began to mumble and snort in the same kele-like manner.
She called our attention by signs - being in the possession of the kele, she had lost the faculty of human speech - and then began to wring the pebble with both hands. Then a continuous row of very small pebbles began to fall from her hands. This lasted for fully five minutes, till quite a heap of small pebbles had collected below, on the skin. The larger pebble, however, remained smooth and intact."
At the request of Bogoras the female shaman repeated this feat with the same success, and all the upper part of the body being naked, it was easy to observe her movements.