Bengal Sultanate, Nasir Al-Din Mahmud Shah (AH 837-864, 1433/34-1459 AD), Silver Tanka, 10.66 gms, NM, Tughra Type, AH 856, Obv. Nasir al-duniya wa’al din Abu al Muzaffar Mahmud Shah Al Sultan, Rev. Al Mua’ayyad bi-ta yid al-rahaman khilafat allah bi’al hujjat wa’al Burhan, G&G #B428, extremely fine, struck on broad flan than usual, nearly complete struck with decorative border coming on flan, extremely rare.