Illuminated manuscript page. Illuminated manu- script page for the month of February from a calendar. The page features illustrations of tree- grafting, fish, writing and, around its border, plants and birds. During the middle ages, book illumination was considered a high art, with gold leaf being used with paints of animal, plant or mineral origins. Photographed from a 15th century French book, Heures de Notre Dame. Books of hours like these were mainly produced during the 14th and 15th century in France and the Low Countries. They were often richly-decorated and usually contained prayers for use at particular times and occasions as well as a calendar.