40004721, Marlborough, 12, Portrait (profile left): Agrippina the Younger (Arundel). Bust of Ariadne or a maenad, ivy-wreathed., Albion Art, Japan, Boardman, J., Scarisbrick, D., Wagner C., Zwierlein-Diehl, E: The Marlborough Gems (2009), Story-Maskelyne, M.H.: The Marlborough Gems (1870), no. 12, Cameo, Sardonyx, 17th century (?)