Here is a nice posthumous issue of Constantius I, struck by Maxentius. RIC mistakenly gives the obverse legend as ending with PIO.
It is ex- Dattari. Giovanni Dattari (1858- 1923) is best known for his Alexandrian coin collection. His family moved to Egypt and as a youth he became interested in antiquities and numismatics.
Coins from his collection have been turning up for sale in auctions since the 70's; but recently a lot have been sold. Jesus Vico has auctioned many, including the example below which just sold for $197.50
Constantius I
A.D. 307- 309
25mm 6.2gm
DIVO CONSTNATIO AVG; veiled bust right.
MEMORIA DIVI CONSTANTI; Eagle, with wings spread, standing facing on square, two door- doored altar enclosure.
In ex. AQΓ
RIC VI Aquileia 127
