John the Baptist is very often shown on altarpieces designed for churches dedicated to him, or there was some other connection of patronage.
St. John's birth, unlike the Nativity of Jesus, taking place in a wealthy domestic scenario became an increasingly subject popular in the late Middle Ages. The beheading of St. John the Baptist in15th century scenes is also shown with the dance of Salome. The artists' interest clearly shows the life of Herod's court as much as the death of John the Baptist. Salome bearing John's head on a platter became an equal subject for the Northern Renaissance John preaching in a landscape setting was popular in Dutch art. He is also depicted as an ascetic wearing camel hair and with a staff and scroll inscribed "Ecce Agnus Dei" (Latin, "Behold the Lamb of God" - John 1:29) or bearing a book or dish with a lamb on it. In Orthodox icons, he has angel's wings, since Mark 1:2 applies to him a prophecy about an ???e??? (angelos), a word that can mean a messenger, but also an angel.
9http://www.stjohn.webhero.com/medal.htm
In art Saint John is represented both as prophet and baptizer: His image is seen on wall-paintings, stained-glass windows, bench-ends, and statues, dressed in skins and pointing to the lamb while carrying a long cross in the other hand. St. John the Baptist medals and Saint John pendants are popular religious jewellery.