Praying where the walls are plastered with dung

Question

What is [the ruling] on having the walls of mud-built mosques plastered with clay mixed with dung and left to rot, given that dung is a heavy impurity (najasa ghaliza)? And what is [the ruling] on praying in such mosques?

Answer

If the dung is little and the clay much, and no trace of the dung is apparent, then prayer there is valid: the jurists have recorded latitude [in this].

Source: Fatawa Mahmudiyya

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