The composition derives from the picture of 1651 (private collection; see L. Salerno, I Dipinti del Guercino, Rome, 1988, pp. 356-7, no. 287, illustrated and pl. 29). In the original, the mantle worn over the Sibyl's shoulder is blue, whilst the lining of her gown is pink. The colours in the present work show that it must have been copied from the version in the Palatine Gallery, Florence (inv. no. P. 788), long considered an autograph work until catalogued by Salerno as a studio copy (loc. cit.).