The "ROMAN EMPIRE Licinius I, AD 308-324 BI Reduced Nummus" refers to a type of ancient Roman coin minted during the reign of Licinius I, a Roman emperor who co-ruled with Constantine the Great. These coins, also known as BI Reduced Nummus or BI follis, were made of billon (a silver-copper alloy) and were smaller in size and value than earlier folles. Licinius I ruled from AD 308 to 324, and his reign was marked by both cooperation and conflict with Constantine.