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Friday Mosque of Na'in
In recent investigations, carried out by Iranian Cultual Heritage Organization, a lapis lazuli and gold inscription, dating back to the 2nd century, was found beneath the carved stucco decoration of the prayer niche. Therefore the original building of the mosque, which comprised the major part of the present mosque, was erected in 2nd century. The entarances of original mosque were located on either side of the northeastern ivan, providing access along a direction facing qibleh.
(Source: Cyclopedia of Iranian Islamic Architecture, Vol. 8, P. 79)