If an iqtāʿ is valid and the ruler wishes to reclaim it from its grantee, he may do so with respect to any year after the current one, and the grantee’s stipend returns to the Dīwān al-ʿAṭāyā (the grants register). As for the year currently in progress, the matter must be considered. If his stipend falls due during that year before its kharaj falls due, it may not be reclaimed from him for that year, since he is entitled to its kharaj as part of his stipend. But if its kharaj falls due before his stipend, it may be reclaimed from him, because advancing a deferred payment, although permissible, is not obligatory.
As for the stipends of those other than the army, when kharaj revenue is assigned to them in payment of those stipends, they fall into three categories.
The first is those who are paid for nonpermanent work, such as officials responsible for public services and kharaj collectors. An iqtāʿ of their stipends is invalid. Whatever they receive from the kharaj revenue is merely a designation of it as the source of payment and an assignment against it, made after the stipend has become due and the kharaj has fallen due.
The second category is those who are paid for permanent work, but whose stipends function as a jʿālah (remuneration for a service). These are those engaged in religious services that may validly be performed voluntarily when compensation is offered for them, such as muezzins and imams. Whatever is allotted to them from their stipends is merely a designation of that revenue as the source of payment and an assignment against it; it is not an iqtāʿ.
The third category is those who are paid for permanent work and whose stipends function as wages. These are those whose work is not validly undertaken except through authority and official appointment, such as judges, governors, and scribes of the administrative registers. It is permissible to assign them one year’s kharaj as their stipends. The permissibility of assigning them more than one year admits of two views. The first is that it is permissible, as it is for the army. The second is that it is not permissible, because they may be dismissed and replaced.
As for assigning mines as iqtāʿs—mines being tracts in which Allah Most High has deposited mineral substances in the earth—they are of two types: surface mines and subterranean mines. Surface mines are those whose deposited mineral substance is exposed, such as mines of antimony used for kohl, salt, and naphtha. Such mines are like water, which may not be assigned as an iqtāʿ. People have equal access to them, and whoever comes to them may take from them.
This was explicitly stated in a report transmitted by Harb. He was asked about the hadith that the Prophet (peace and blessings be upon him) had assigned a man the salt mine at Maʾrib. He was told, “It is like freely available water.” The Prophet then revoked the grant and said: “A salt mine frequented by people in the open country, from which they take salt, is not the property of anyone. The ruler took it and assigned it to a man, who barred the people from it. He disapproved of this and said, ‘This belongs to the Muslims.’”