Antonello Grifo della Moneta, also known as Antonello di Pietro, was employed in the Venetian mint from 1454 (possibly from 1447) until 1484. He was both a goldsmith and a die-cutter. The attribution of NGA 1957.14.730.a,b to him was made by George Francis Hill as a work distinct from NGA 1957.14.729.a,b by Antonio Gambello.
[This is the artist's biography published in the NGA systematic catalogue of Renaissance medals.]