According to J. Gacki's description, "about five wiorsts from Jedlnia, Kozienice county (...) in the government forest, in a place called Piecnik, there is a stone three cubits long, one and a half cubits thick at one end and a quarter cubit at the other end, bearing some traces."
The stone was said to lie on the Rokietka River, near today's road to Brzustow. It could not be found during a field search. Probably it lay in the charming area called "Kamyk", today part of Pionki.
According to a legend, the stone was supposed to bear the imprint of the shoe of a local parson from Jedlnia, who, courting the forest stretching all the way to the big stone, stood on it for so long until he imprinted his footprint in it. In this case, the stone with the foot would be a boundary marker.
D. Czernicka-Chodkowska mentions an erratic boulder in Jedlnia Koscielna, set next to the buildings. I have not been able to discover it in the field.
Sources of information: Gacki 1874, 133; Baruch 1907, 32; Czernicka-Chodkowska 1980, 30; field queries