Venetian glassmaker who, thanks to the negotiations by Grand Duke Cosimo I de' Medici (1519-1574) with the Venetian Republic, was called to Florence as a crystal-maker. Documented in the Tuscan capital as early as September 1569, Bortolo remained there for about fourteen years and introduced new techniques. The inventory of his workshop records reticello [filigree] glass, engraved glass, ice glass, a gilded tray, and weave-pattern vases with handles."