Giorgio Vasari, Lives of the Most Excellent Painters… (1850)
“ In the pictures on the walls, moreover, of which there are five, the attitudes of the figures are very beautiful, and the whole work gives proof of a rich invention and much judgment. But as Buonamico, desirous of imparting transparency to his carnations, was in the habit of using a blue lake, as we see in this work, which in the course of time produces a salt, whereby the white and other colours are corroded and destroyed, so it is not wonderful that these paintings are much injured, while many others, executed long before, are still perfectly well preserved. ”
