Sultanate: Bengal
Ruler: Jalal al din Muhammad
Type: Tughra on both sides
Mint: Muazzamabad (Not listed)
Date: ???
A wonderfully clear and well centred strike. I can't be of any help in this area, but I know a good coin when I see one. The characteristic toughras - I had not seen them before you started showing them - are an interesting and lively aspect of these series. Maybe they were part of a development from normal writing to a stylised, highly formal shape...
Peter