Province Bithynia-Pontus
City Nicaea 
Region Bithynia
Reign Severus Alexander
Obverse inscription Μ ΑΥΡ ⳞΕΥΗ ΑΛΕΖΑΝΔΡΟⳞ ΑΥΓ
Obverse design laureate head of Severus Alexander, r., with drapery
Reverse inscription ΝΙΚΑΙΕΩΝ
Reverse design Pan advancing nude, l., holding reed and palm


Reference Munzen & Medaillen
Diameter 28
Note the same coin as Boston?