SASANIAN KINGS. Khosrau I (Anushakravan) 531-579 AD. Silver Drachm (3.70 gm; 31 mm). AS (Asuristan or Aspanvar in Ctesiphon region) mint, year 37. Obverse; Khosrau's bust turning right with standard legends. reverse; fire altar with attendants. Sunrise 970. Choice EF.