Sultans of Malwa, Muhammad I (1435-36), Tanka, 10.01g, Shadiabad, AH840 (G&G M13), about very fine, very rare.
Muhammad's reign covered the years 838-839 but gold and silver Tankas of the present type are dated AH840. This coin was either issued posthumously by adherents of Muhammad or his son, Mas'ud Khan, or Muhammad's reign actually extended into the year AH840.
Estimate: £800 - £1,000