A traditional steel plug-and-feather splitting set used to detach marble during roughing by driving a tapered wedge between two shaped metal feathers placed in drilled holes.
Punciotto is a traditional marble-splitting device used during sbozzatura. It consists of a long steel wedge and two semicircular feathers or wings that thicken toward one end. A row of holes is drilled along the intended break line; the feathers are inserted into each hole and the central wedge is struck until the stone splits.
Etymology
Italian workshop term; also encountered in local variants such as pucciotto/punciotto.
Sculptor Notes
The method converts a row of small drilled holes into a controlled fracture plane. Hole spacing, direction, and the sequence of blows determine whether the split follows the intended line or runs unpredictably.
References
https://levocidelmarmo.sns.it/scheda_oggetti_relazione.php?denom=punciotto&id=17