Depiction of a Cossack from 1701 and similar clubs excavated at Berestechko battle site (1651).
There is also description by Kitowicz of how polish peasants made their clubs studded with flint shards. In original:
Laska drewniana krzemieniem nasadzana; który krzemień zasadzali za skóre drzewa na pniu stojącego; gdy już dobrze wrósł krzemień w drzewo, dopiero go spuszczali i lasko robili.
Wooden staff studded with flint; this flint they put behind bark of growing tree; after it is well grown into the tree, they cut it and make a staff.