Leonardo da Vinci's 'Lady with an Ermine' (c. 1489) is one of only four portraits of women he painted. Recent technology using 'Layer Amplification Method' (LAM) revealed that Leonardo actually painted the portrait in three distinct stages. In the first version, there was no ermine at all. In the second, he added a small, grey ermine, and in the third, he transformed it into the large, muscular, white animal we see today. The ermine was a symbol of purity but also a pun on the sitter’s surname, Cecilia Gallerani (the Greek word for ermine is 'galê'). It also represented her lover, Ludovico Sforza, who was a member of the Order of the Ermine. This discovery proves that Leonardo was a perfectionist who constantly revised his compositions to add deeper layers of meaning and political symbolism.