Who is Callandrino from the collection, Italian Stories = Novelle Italiane?

Calandrino is a painter who has a reputation for being gullible. His friends take advantage of him and trick him into searching for a fictional stone that grants its possessor the power of invisibility. While on this expedition, they pretend that they cannot see him, making him believe he has the stone. However, when he returns home, his wife yells at him for coming home late and he believes that she has broken the spell on his stone.