billon tetradrachm 
of Maximianus,  minted in year 1 (286/7 AD) at Alexandria.  
The reverse is Elpis (Spes),  walking left,  holding a flower. 
"L", "B" and star in the field.  But the online reference I 
checked says that it's actually year 2,  and the "B" suggests 
that the online reference is right (The Alexandria mint used 
Greek letters to indicate the year,  so a year 1 coin should 
have an "A").  The online references also say that it's made 
of potin,  not billon (billon has at least some silver,  but 
the Romans had probably cut the percentage of silver to "0" by 
the time this coin was minted).