Bengal Sultanate, Shams ud-din Ahmad Shah ( AH 836-867/14 AD), Firuzabad Mint (?), Silver Tanka, Obv: Shams ud dunya wa'l din Abu'l Muzaffar Ahmad Shah bin Muhammad Shah al-sultan, Rev: Nasir amir al-mu'minin ghawth al-islam wa'l muslimin khulda mulkahu, 9.8g, 27.73mm, (G&G # B392A), usual chop with multiple shroff marks, about very fine, Extremely Rare.