RR silver tanka of Muhammad Shah (1415-1432), Arsah Chatgaon (Chittagong) mint, Bengal Sultanate, India (B-347)

Inscriptions in Tughra characters on both sides: Al-Muayyad bi-tayid al-rahman Jalal al-din Mohammed Shah al-Sultan  in Tughra / Shahada, mint and date in the margin. Arsah Chatgaon mint (modern Chittagong in Bangladesh), dated to 829 AH = 1425 AD. 30mm, 10.18 grams. "The coins of Indian Sultanates" #B347.

Excellent large silver coin. EXTREMELY rare, especially with a clear mint name like on this one.