Bengal Sultanate (1203-1576) Silver tanka of Ghiyas ud-Din Mahmud Shah (939-945 AH/1532-1538 AD), Barbakabad mint, Bengal. Rare!

Inscriptions on both sides: Al-sultan bin-al-sultan ghiyath as dunya wal din abul muzaffar mahmud shah al-sultan bin husain shah al-sultan khallada allah mulkahu wa sultanahu, "Badr Shahi" within a circle on both sides Barbakabad mint, dated "33" (= 933 AH = 1526 AD) (). Excellent large silver coin, very attractive, thick and heavy. Rare mint! 25mm in diameter (large!!!), 10.7 g."The coins of the Indian Sultanates" B-897. The "Badr Shahi" coins seem to pre-date Mahmud's reign - it appears than between AH 933 and 939 he took part in governing the Kingdom and was allowed to issue coins in his own name