Claudius AV aureus 20mm, 7.77 g. Rome, AD 46-47. 

TI CLAVD CAESAR AVG P M TR P VI IMP XI (insterspersed with dots), laureate head right.
IMPER RECEPT along top of circular wall enclosing the
 Praetorian camp composed of tall brick battlements around a 
central shrine, within which stands a soldier standing left, 
holding spear and gesturing toward a legionary eagle (aquila) on a standard affixed with three crescents. 

RIC 36, BMCRE 37, Calicó 362; Sear 1832 var (trib. year).
Extremely rare, rated R4. 

Contributed by Mike Festa, Feb. 2015.