Iranian rial banknotes bearing a portrait of the late Ayatollah Khomeini sit on the stand of an Iraqi money dealer in Arbil. If the six great powers negotiating with Iran reach an agreement on the nuclear issue by the July 20th deadline, the rial is sure to appreciate. Photograph: Karim Sahib/AFP/Getty Images

The face of Ayatollah Ruhollah Khomeini, the father of Iran’s Islamic revolution, stares at you from one side of the 50,000 rial banknote. On the othe(...)