A small pointed hand tool, sometimes double-pointed, rotated by hand to make small holes in which precise reference points are marked during marble modeling.
Concolino is a small pointed chisel-like tool used during smodellatura. According to Le voci del marmo, it may have one or two points and is rotated by hand to excavate small holes where measured points are recorded in the marble.
Its function is therefore closely connected to accurate point transfer rather than bulk material removal.
Etymology
Italian workshop term.
Sculptor Notes
The concolino belongs to the precision stage of copying. Its small holes preserve a measured location while surrounding marble is gradually reduced toward the intended surface.
References
https://levocidelmarmo.sns.it/scheda_oggetti_relazione.php?denom=concolino&id=30