Mohammad Reza Shah Pahlavi (1919 - 1980) was the king of Iran (Shah of Iran) from 1941 until his overthrow by the Islamic Revolution in February 1979. He was the second and last monarch of the House of Pahlavi of the Iranian monarchy. Farah Diba was is Shah's second wife (now widow), preceded by Soraya Esfandiary-Bakhtiari, the Shah's first wife. Soraya and Mohammad Reza dissolved their marriage in 1958 because they could not have children.
For many years Pahlavi and his wife appear on the front of commemorative Nowruz (Norouz, Norooz, New Year) medals. Those before 1958 show Soraya and those after 1959 show Farah. The date is shown in eastern Arabic numerals under the royal couple. To convert the date from Islamic (AH) to Gregorian (AD) note that AH1335 is 1956AD, AH1337 is 1958AD, and AH1357 is 1978AD. The medals are minted in both silver and gold.
These medals are worth their weight in silver or gold. The trouble is, the actual weight of precious metal is not precisely the same from year to year. If you have access to a jeweler's scale, it is a good idea to weigh your specific medal. The silver medals are about 100 percent pure; gold medals are about 90 percent pure. Roughly, for silver at $16 US dollars per troy ounce and gold at $1200 per ounce:
fully uncirculated: $40
fully uncirculated: $1200
The medals with Soraya (before 1959) are somewhat more valuable than the medals with Farah.