Bengal Sultanate, Silver tanka of Nasir al-Din Mahmud Shah (1434-1459 AD), al-Firuzabad mint, date not clear, G&G B433, 10.63g. Obv: Arabic legend al-Sultan al-'Adil Nasir al-Dunya wa al-Din Abu al-Mujahid Mahmud al-Sultan. Rev: Kalima in circle, mint and AH date in words in the margin.Good Very fine, Very scarce.