The Dirhum, or Dirham, as the word is sometimes given, is a silver coin, the shape of which resembled that of a date-stone. During the khilafat of  'Umar, it was changed to a circular form and in the time of Zubayr it was impressed with the words Allahu (God), barakat (blessing). Hajjaj stamped upon it the chapter of the Qur'an called Ikhlas; and others say that he imprinted it with his own name. Others assert, that 'Umar was the first who stamped an impression on dirhams; whilst, according to some Greek, Khusravite and Himyarite dirhams were in circulation at the time of 'Abdu 'l-Malik, the son Marwan, by whose order Hajjaj, the son of Yusuf, had struck dirhams. Some say that Hajjaj refined the base dirhams and coined them with the words Allahu ahad (God is one), and Allahu as-samad (God is eternal); and these dirhams were called makruha (abominable), because God's holy name was thereby dishonoured, unless this term be a corruption of some other name. After Hajjaj, at the time of the reign of Yazid bin 'Abdu '1-Malik, 'Umar bin Hubayrah coined in the kingdom of 'Iraq better dirhams than Hajjaj had made; and afterwards Khalid bin 'Abdu 'llah Qasri, when governor of Iraq, made them still finer, but they were brought to the highest degree of purity by Yusuf son of 'Umar. Again, it has been said that Mus'ab bin Zubayr was the first who struck dirhams. Various accounts are given of their weights; some saying that they were of ten or nine, or six or five misqals; whilst others give the weights of twenty, twelve, and ten qirats, asserting at the same time that 'Umar had taken a dirham of each kind, and formed a coin of fourteen qirats, being the third part of the aggregate sum. It is likewise said that at the time of 'Umar there were current several kinds of dirhams: first, some of eight dangs, which were called baghli, after Ras Baghl, who was an assay-master, and who struck dirhams by the command of 'Umar; but others call them baghalli, from baghal, which is the name of a village; secondly, some of four dangs, which were called tabri; thirdly, some of three dangs, which were known as maghribi; and lastly, some of one dang, named yamani, the half of which four kinds 'Umar is said to have taken as a uniform average weight. Fazil of Khujand says that in former days dirhams had been of two kinds: first, full ones of eight and six dangs (1 dang of his=2 qirats; 1 qirat= 2 tassuj; 1 tassuj=2 habbah); and secondly, deficient ones of four dangs and a fraction. Some hold different opinions on this subject.

The Dinar is a gold coin, weighing one misqal, i.e. 1.75 dirhams, as they put 1 misqal= 6 dang; 1 dang= 4 tassuj; 1 tassuj= 2 habbas; 1 habba= 2 javs (barley grains); 1 jav= 6 khardals (mustard-grain); 1 khardal= 12 fals; 1 fals= 6 fatils; 1 fatil= 6 naqirs; 1 naqir= 6 qitmirs; and 1 qitmir= 12 tras. One misqal, by this calculation, would be equal to 96 barley grains. Misqal is a weight used in weighing gold; and it is also the name of the coin. From some ancient writings it appears that the Greek misqal is out of use, and weighs two qirats less than this; and that the Greek dirham differs likewise from others, being less in weight by .16 or .25 misqat.