The painting was given to the Museum in 1983 by Henry H. Reichhold, a summer resident of Prouts Neck, who purchased the work in the 1960s after the death of its European owner. Subsequently, La Gioconda was analyzed at the Straus Center for Conservation and Technical Studies at Harvard University. Conservators determined that the painting was executed before 1510, but they were unable to confirm or refute Leonardos hand in its creation.
Unlike a true copy, the Museums Mona Lisa differs from the original in size, composition of background landscape, and, most notably, the absence of the enigmatic smiledetails which suggest an early study rather than a simple reproduction. Regardless of the true authorship of the painting, La Gioconda brings into sharp focus the kinds of problems facing conservators and art historians today, and it is a compelling work of undeniable artistic quality on its own.
Source: Portland Maine Museum of Art at (207) 775-6148 ext. 3227.http://www.portlandmuseum.org/Da%20Vinci.htm