Billon tanka of 80 rati. Persian inscriptions on both sides: Ibrahim shah al-sultani khulidat mamlakatahu / al-khalifa amir al-mu minin khulidat khilafatuhu. Dated to 842 AH = 1438 AD. 18mm, 9.41 grams. Angular style and no mint-name. White colour, decent quality billon. "The Coins of the Indian Sultanates" J-6; Rajgor 2703.
The Jaunpur Sultanate attained its greatest height under the younger brother of Mubarak Shah, who ruled as Shams ud-din Ibrahim Shah (ruled 1402-1440). To the east, his kingdom extended to Bihar, and to the west, to Kanauj; he even marched on Delhi at one point. Under the aegis of a Muslim holy man named Muhammad Jaunpuri Imam Mahdi, he threatened the Sultanate of Bengal under Raja Ganesha. Ibrahim Shah was a patron of Islamic learning and established a number of colleges for this purpose. A large number of scholarly works on Islamic theology and law was produced during his reign, which include the Hashiah-i-Hindi, the Bahar-ul-Mawwaj and the Fatwa-i-Ibrahim Shahi. He constructed a number of monuments in a new regional style of architecture known as the Sharqi. During his reign, Sultan Nasiruddin Mahmud Shah II Tughluq took refuge in Jaunpur in order to get rid of the control of Mallu Iqbal over him. But he did not treat Sultan Mahmud Shah well. As a result, his relations with the Sultan became bitter and Mahmud Shah occupied Kanauj. In 1407 he tried to recover Kanauj but failed. His attempt to conquer Bengal also failed. He was succeeded by his eldest son Mahmud Shah after his death.