The picture on the cover of Maid of Heaven is from the famous painting of Joan of Arc by Jules Bastien-Lepage painted in 1879.
The original painting is on public display at the Metropolitan Museum of Art in New York city.
You may notice that the colors in the picture on the cover of Maid of Heaven are much brighter and more vivid.
This is because the picture was digitally enhanced to look as close as possible to the original when it was first painted.
To get an idea of what the artist intended his painting to look like you can read an excellent review by clicking Here. For more information
on the painting you can also go Here. For biographical information on Jules Bastien-Lepage click Here.