The first tablet is illustrated with St. Paul bearing a serpent, the second tablet is inscribed with a Maltese cross, the third depicts a hermit adoring a crucifix in a cave, the fourth is an illustration of a ship (perhaps the one that St. Paul travelled to Malta in), the fifth tablet bears an illustration of John the Baptist and the Lamb and the sixth is also of a ship
For terra sigillata see further: D. Cowen and W.H. Helfand, Pharmacy an illustrated history, New York 1990, p. 34
Karl H. Dannenfeldt, The introduction of a new sixteenth century drug: terra silesiaca, Medical History 1984, no. 28, pp. 174-188