A rare drawing of the Italian Renaissance painter Sandro Botticelli (Study for a Seated St Joseph) was sold for $2.2 million.

The drawing is considered to be the only work of Botticelli which is associated with one of his paintings and the only one that remained until now in a private collection.

The owner was Piasecka Barbara Johnson, who has passed away. She engaged in charities and was the wife of John Seward Johnson, heir of the pharmaceutical company “Johnson & Johnson”.

The money raised will go to Barbara Piasecka Johnson Foundation, which helps children with autism.

Johnson had bought the drawing in 1988 in New York City for about $88,000.