Maurice Tiberius AE4. Constantinople, ca 583-584 AD. 

Obv: No legend, Monogram 60 of Maurice Tiberius
Rev: No legend, Dodd Monogram 30/31 of City Prefect 
Iwannov. 

See www.forumancientcoins.com/numiswiki/view.asp?key=Monogram
for illustrations of monograms on Byzantine coins.

Contributed by George Clegg (biggyg2), July, 2009