Okay, I have it:

AR Denarius – Coelia 2 – C. Coelius Caldus, 104 BC.

Obv: Helmeted head of Roma left.
Rx: Victory charging in biga left; control: • G above; C•COIL below horses; in ex, CALD.

Crawford/RRC 318/1a; Sydenham/CRR 582; SRCV 196; BMC 1435-62; Babelon/RSC Coelia 2.

Mark