Bengal Sultanate, Rukn Al-Din Barbak Shah (AH 864-879, 1459-1474 AD), Silver Tanka, Three Chambers Type, 10.09 gms, Barbakabad arsah Sikandrabad Mint, ND, Obv. al-azam al-muazzam Barbak Shah al-sultan bin Mahmud Shah al-sultan, Rev. Kalima Shahada and al-alim al-adil Barbakabad arsah Sikandrabad, Unlisted Mint in G&G, very fine, extremely rare.