Gratian AR Siliqua, 378-383 AD. Siscia mint. 

Obv: DN GRATIA-NVS PF AVG, pearl diademed, draped, cuirassed bust right. 
Rev: VOT XV MVLT XX in four lines within wreath with dot in badge. 

Mintmark SISCP runic S.

RIC IX Siscia 25; RSC 72g; Sear -. 

Courtesy of TimeLine Auctions (www.timelineauctions.com), October, 2012