What material should be used to cover the niche (*lahd*)?

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Bricks (*labin*) should be placed to cover the niche, and the gaps should be sealed with clay so that soil does not enter. If reeds (*qasab*) are used instead of bricks, it is also good, as Al-Sha'bi reported seeing the Muhajirun favoring this for the Prophet's (peace be upon him) grave. Ahmad initially favored bricks but later leaned towards preferring reeds. The most authentic narrations from Abu Abdullah (Ahmad) favor bricks, citing Sa'd's narration, as Sa'd was present while Al-Sha'bi was not.