The main inscription which runs around the three sides and then continues in two lines at the base of the panel is from the Qur'an, sura ix, al-tauba, v.18. The third line of the inscription at the base of the panel is the signature of the maker, Muhammad b. Firuz al-....
This unusual turquoise glazed mihrab differs in many ways from the more regularly encountered mihrab tiles such as that offered in lot 290 which has an opaque tin glaze and the soft rounded decoration. The execution of this has much more in common with the glazed and unglazed pottery of the Umayyad period (see lot 289 in this sale) and the similarly made pieces of subsequent centuries.
A number of unglazed fragments of such vessels with comparable calligraphy were excavated at Nishapur. The calligraphy in particular is similar to that found on the shoulders of two jugs dateable to the 11th or 12th century (Wilkinson, Charles K.: Nisphapur: Pottery of the Early Islamic Period, Greenwich, Conn, n.d., nos.161 and 165, pp.330 and 358). A smaller fragment found at Nishapur shows that, as in the present tile, the potters occasionally dotted or marked the lines of the inscription (Wilkinson, op.cit, no.145, pp.327 and 356).
The overall design of the present mihrab tile however has more in common with the carved marble panels from Ghazni. The combination of a horseshoe arch supported on baluster columns enclosing a large pendant mosque lamp is found for example on one carved marble mihrab panel in the David Collection, (Folsach, Kjeld v.: Islamic Art, The David Collection, Copenhagen, 1990, no.272, p.165). That example even has the chains of the lamps flanked by the repeated word Allah while the motif on the upper band of the present tile makes more sense when one compares it with the almost muqarnas-like cresting on the Afghan marble.
A thermoluminescence test performed by Oxford Authentication confirms the proposed dating of this lot.