A T-shaped support used with a pointing apparatus to establish three fixed reference points between a model and its stone copy.
Croce a T (“T-cross”) is a wooden support used with the traditional pointing apparatus. Le voci del marmo describes it as an inverted T-shaped structure on which three nails are fixed with plaster after the cross is positioned on the model; these correspond to the three principal reference points used by the pointing device.
The support allows the apparatus to be repositioned reproducibly between model and stone.
Etymology
Italian: croce, “cross,” + the letter T.
Sculptor Notes
The Croce a T demonstrates that pointing is fundamentally geometric. Before a surface point can be transferred, the measuring instrument itself must occupy a repeatable position in space.
References
https://levocidelmarmo.sns.it/scheda_oggetti_relazione.php?denom=croce+a+t&id=49