(b Siena, July 18, 1866; d Siena, Jan 23, 1946).
Italian forger, restorer and writer. He is best known for his autobiography, a broad panoramic portrait of life in provincial Italy at the end of the 19th century, which conveys something of the disquiet concerning the loss of Italy’s prestige. He also worked as a skilful forger and restorer at a time when the distinctions between the two activities were blurred. Much of his success as a forger was due to the fact that he imitated either the works of lesser painters (such as Sano di Pietro) or the undistinguished works of more famous artists, which could deceive even a connoisseur. A typical example is his copy of Cecco di Pietro’s Agnano polyptych (Pisa, Mus. N. S Matteo), created as a fraudulent substitution for the original (Rome, Pal. Venezia). Few of Joni’s fakes have stood the test of time, despite the fact that he was in contact with such critics and collectors as Francis Mason Perkins and Robert Langton Douglas. Research into collecting and the art market in late 19th-century America has identified Joni’s role as a restorer in such works as ...