Romulus Augustus. October 475 - September 476 AD. AV Tremissis, 1.46 g. Rome mint. 

Pearl-diademed, draped and cuirassed bust right.
Cross within wreath.
Mintmark COMOB. 

RIC X 3411 (same obverse die); cf. Depeyrot 87/1.
Extremely rare.

With permission of cngcoins.com, auction 66, Lot 1661.
Sold For $20,000.