here is a nice Festival of Isis coin-
Festival of Isis.
Mid-4th century A.D.
13mm 1.3gm
VOTA PVBLICA; draped bust of Serapis right, wearing modius.
VOTA PVBLICA; Harpocrates standing left, putting right forefinger to his mouth and holding cornucopia.
Rome mint
Alföldi 120; Vagi 3385
Harpocrates was the Greek god of silence and confidentiality. He was adapted from the Egyptian god Horus, who was the son of Isis and Osiris.
The best reference for these coins is still Alföldi's 1937 dissertation
A Festival of Isis in Rome under the Christian Emperors of the IVth Centuryhttp://www.constantinethegreatcoins.com/articles/Alfoldi_A_Festival_of_Isis_in_Rome.pdfa good book that also touches on these coins and surrounding circumstances of the issue of these Festival of Isis coins, also by Alföldi
Alföldi,
The Conversion of Constantine and Pagan Rome. translated by Harold Mattingly. Oxford University Press, 1998
