There are two different types of this coin, one with era date in field above (type 1) and the other with date in exerque (type 2). The coin i am showing today is of type 1 and extremely rare. I managed to track down 13 other coins of type 1 using all the major websites and museums. Eight of the coins are undatable due to their bad condition, four are year 40 and one is year 36. My coin appears to be the first of it´s type that can be clearly dated as year 54.