A slightly older but important article by Llewellyn-Jones dealing with the imagery of Achaemenid period seals and gemstones:
Llewellyn-Jones, Lloyd. 2010. The big and beautiful women of Asia: Ethnic conceptions of ideal beauty in Achaemenid period seals and gemstones. In Hales, Shelley & Tamar Hodos (eds.), Material culture and social identities in the ancient world. Cambridge: CUP.
Read the article here.