Estimating the Value of Derham and Dinar in Muslim's Economic History

Before the appearance of Islam, Dinar and Derham were the currencies of Byzantine and Iran, recpectively. These two currencies were current in pre-Islamic Arabia and continued to be the currencies of primary Islamic states. In 74 (AH) Islamic Dinar and Derham were coined. Estimating the value of Dinar and Derham is a matter of considerable importance to those doing research in Islamic Economics. The present article tends to estimate the value of these two currencies using two methods of purchasing power and natural value. The findings from the research show that each Dinar worths 293 to 350 thousand rials.