Bengal Sultanate, Rukn ud-din Barbak Shah (AH 864-879/1459-1474 AD), Dar al Darb Mint, Silver Tanka, AH 86X, Obv: Rukn ud dunya wa'l din Abu'l Muzaffar Barbak Shah al-sultan bin Mahmud Shah al sultan, Rev: al-muayyud bitayid-ur-rehman khalifat allah bil hujjat wal burhan, 10.4g, 26.00mm, (G&G # B506), about fine, usual punches.