Italian goldsmith. Trained in the workshop of the Florentine goldsmith Francesco di Niccolò, he matriculated in the goldsmiths' guild, the Arte della Seta, in 1358. In 1361 Francesco was commissioned to execute nine narrative reliefs of episodes from the Old Testament for the antependium of the silver altar of S Jacopo in Pistoia. Documents of 13 April 1363 and 30 June 1364 indicate that Leonardo assisted with this work, which was completed in 1364. The relief panels were originally to the left of the scenes on the main face of the antependium, to which they relate chronologically and iconographically: the altarpiece was dismantled in 1381, and the two lateral faces were transposed. Francesco was the principal author of the reliefs, but in the last two panels depicting the Birth of the Virgin and Betrothal of the Virgin a different hand has been identified, possibly that of Leonardo. On 16 January 1366 Leonardo and Betto di Geri (fl 1366-1402) received the prestigious commission from the Arte di Calimala to make a silver altar decorated with scenes from the Life of St John the Baptist (Florence, Museo dell'Opera del Duomo) for the Florentine Baptistery. In 1367, while still working on some panels for the silver altar in Florence, Leonardo was commissioned to execute nine scenes from the Life of St James the Greater for the right side (now placed on the left) of the altar at Pistoia. This panel is inscribed DETTE OPERE SVB ANNO DOMINI MCCCLXXI PER ME LEONARDVM SER IOHANIS DE FRORENTIA AURIFICIS. It was because of this inscription that Vasari believed, incorrectly, that Leonardo had executed the entire altarpiece. //