Al-mutawwakkil ala'l rahman bahlul shah sultan bi-hadrat Dehli // Fi zaman amir al-muminin khulidat khalifarahu and date 860 (= 1456 CE). 20mm, 9.42 grams. Delhi mint. G/G #D690. 

High-silver billon tanka, excellent quality. Much scarcer than Goron/Goenka indicated.