This is a very rare gold ducat of Venice struck in the name of Doge Giovanni Mocenigo. Not to be confused with Tomasso Mocenigo, who was Doge about 50 years earlier, and who's ducats are among the most common. This is one of only 6 ducats graded by NGC of this Doge, with a 7th specimen certified by NGC but not grade-able. PCGS has graded only two of these ass of 2020, one in MS-63 and one in AU-58. 

A great piece to add to any collection. This item will ship via 2nd day air within 1 day of cleared payment. 

Giovanni Ser di Mocenigo, Jr. (1409 - November 4, 1485), Pietro Mocenigo's brother, was doge of Venice from 1478 to 1485. He fought at sea against the Ottoman Sultan Mehmed II and on land against Ercole I d'Este, duke of Ferrara, from whom he recaptured Rovigo and the Polesine.