What is the ruling on finding *rikaz* (buried treasure) in the land of non-Muslims?

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If one finds *rikaz* in the territory of non-Muslims (*dar al-kufr*), the ruling depends on the means of retrieval. If a single person can acquire it by themselves, the ruling is the same as finding it in the land of Islam: one-fifth (al-khums) is due, and the remainder belongs to the finder. However, if its retrieval requires the force of the entire Muslim army, then it constitutes *ghanima* (spoils of war). This view is held by Malik, Al-Awza'i, and Al-Layth. The evidence provided is the narration of Asim bin Kulayb, from Abu al-Jawiriyyah al-Harami, who stated that he found a jar of gold in the land of the Romans during Mu'awiyah's time. When brought to the commander, it was divided among the Muslims, and the commander stated, "Were it not that I heard the Messenger of Allah (peace be upon him) say: 'There is no extra share (*nafl*) except after the one-fifth,' I would have given it to you." Furthermore, the basis is that this is the wealth of a polytheist (*mushrik*) that has been uncovered through the might of the Muslim army, thus classifying it as *ghanima*, similar to their apparent possessions.