Guacialoti was the son of one Filippo, a resident of Prato whose family was Florentine in origin. Andrea entered the household of Niccolò Palmieri, bishop of Orte, at an unknown date and became a papal scriptor in Rome, a canon of Prato, and a priest of the town of Ajolo (Iolo), near Prato. Guacialoti was well known as a bronze founder. From 1464 he lived mainly in Prato and was commissioned to cast the medal by Bertoldo di Giovanni commemorating the Pazzi Conspiracy of 1478 (NGA 1957.14.846.a,b). He died in 1495 and was buried in Prato.
The artist's medals were all made in Rome; seven are signed, and seven are attributed. His papal portraits include Popes Nicholas V (of about 1455), Calixtus III (NGA 1957.14.802.a,b), Pius II, 1458-1464, and Sixtus IV (NGA 1957.14.803.a,b). The latest dated medal by Guacialoti is that of Alfonso of Aragon, Duke of Calabria (NGA 1988.30.4.a,b) of 1481.
The medals are vigorous in style, the designs frequently supplemented by engraving and the reverses occasionally copied from medals by Pisanello or Cristoforo di Geremia. Two of the portrait types are remarkable: the head of Palmieri (NGA 1957.14.801.a,b) is presented as a Roman republican bust type, and the portrait of Alfonso of Calabria (George Francis Hill, A Corpus of the Italian Medals of the Renaissance before Cellini, 2 vols., London, 1930: no. 745) copies a painted portrait, with considerable success.
[This is the artist's biography published in the NGA systematic catalogue of Renaissance medals.]