Rukn al din Firuz, Silver Tanka, 10.83g, Delhi Mint, AH 633, Three dots in each marginal segment, Arabic legend on both sides, Obv: “al sultan al azam shams al dunya wa’l din al sultan al muazzam rukh al dunya wa’l din Firuz shah”, Rev: “fi ahd” & date (G&G# D90/D91 type, this type not listed in G&G). Very fine, extremely rare.