Roman Republican AR Denarius, M. Carbo, 122 BC. 

Helmeted head of Roma right, branch behind head, X below.
Jupiter in prancing quadriga right, hurling thunderbolt and holding sceptre; M CARBO and ROMA below. 

Babelon Papiria 6. Sydenham 423. Crawford 276/1. 

With permission of Numismatica Ars Classica - Auction 54, Lot 184, March 2010