The importance of Islamic coins
Preface from The Coinage of Islam, by William Kazan

The coins of the Islamic world are primarily religious, political and cultural documents which record history rather than merely recalling it. A classical Muslim coin proclaims the Faith in the One God, Unique and Everlasting and Apostleship of Muhammad, the Messenger of God. It generally also contains a statement of the place and date in which it was struck, and frequently the name of the ruler, his father, heir apparent or political overlords. This enables the student to understand the interrelationships which bound each dynasty to the larger world of Islam, while the religious legends provide clues to the particular branch of the faith to which a ruler belonged.

If the complete series of coins issued by every Muslim dynasty were preserved and published, the historian would be able to list with accuracy the names of each ruler and his principal vassals in every part of the world of Islam from the second century of the Hijra, and determine with considerable accuracy the boundaries of each state at every point in its history.

Why have Muslim coins always been so important? In an age before newspapers, radio and television, the mosque and the coinage were the primary means of communication between a ruler and his people, and statements made through both mediums had the power of law behind them. The protection of God was invoked for the well-being of the sovereign whose name was proclaimed by the khatib, preacher, from the minbar, his seat of authority, to the congregation of the Faithful during the recitation of the Friday sermon, khutba. While outside in the world of daily life the coins, sikka, bearing the sovereign's name and those of the cities under his rule, reminded his subjects of his power and responsibility for their economic needs. A change of ruler was made official when he was first mentioned publicly in the khutba and when the coins were issued in his name. A change in sovereignty was confirmed when the name of the victor was substituted for that of the vanquished on the minbars of the mosques of the newly-conquered town, and coins bearing the name of the new sovereign were distributed after the midday prayer.

The greatest act of disloyalty, indeed of open revolt, took place when a relation or a rebellious vassal substituted his own name for that of his overlord in the khutba and sikka. Thus the Islamic coinage performed the dual function of proclaiming the eternal truth of the Unity of God and the Apostleship of Muhammad, His Prophet, and publishing the current state of political life. In the later middle-ages they were also, on occasion, given a lighter, more purely artistic aspect which revealed the personal aesthetic and even romantic inclinations of the ruler. As such they are both religious treasures and a record of contemporary history whose preservation and study is an important duty for the enlightened and educated Muslim.