Constantinople, Ca. AD 491-518
Anastasius I Av. solidus, Constantinople. D N ANASTA-SIVS P P AVG; helmeted and cuirassed bust, 
three-quarters facing to right, holding spear over shoulder and shield decorated with horseman 
spearing a fallen enemy. Rev. VICTORI-A AVGGG; Victory standing left, holding staff surmounted by reversed Chi-Rho; star in left field; mintmark CONOB. DOC I 6 var. (officina); MIB 6; BN 8 var. (same); SB 4. 
 
Flavius Anastasius, an Imperial official of the Emperor Zeno, ascended to the throne in AD 491 through marriage to Ariadne, the widow of his predecessor. In numismatic terms, Anastasius is most notable for his currency reform of AD 498. This included the introduction of the bronze follis and corresponding smaller denominations, which provided a convenient solution to the tiny and 
impractical bronze issues currently in circulation. 
 
This reform retained the solidus, a gold denomination that was first issued by Constantine I. Solidi such as this example eventually became an international coinage, garnering acceptance and esteem from North Africa to China.

For additional information see: Sear, D. R., 1988, Roman Coins and Their Values: 4th Edition. Spink Books.

Wroth, W., 1908, Catalogue of the Imperial Byzantine Coins in the British Museum. London