Marcus Aurelius, AR denarius mule, poss. ancient imitation.
140 AD. 

AVRELIVS CAESAR AVG PII F COS, bare head right
AEQVITAS AVG, Aequitas standing left, holding scales and 
rod. 
Unpublished mule or ancient imitation with reverse of Antoninus Pius RIC 61. 

Contributed by Laurie Eades, April 2012.

Not in RIC, Cohen ed. 1, Cohen ed. 2, Belfort's additions 
to Cohen, Evans additions to Cohen or RSC. 

This reverse was used for Ant. Pius in 140-143 AD 
and the obverse legend for Marcus Aurelius was used 
in 140 AD, so the times coincide.

What may point to it being an ancient imitation, is the 
sceptre Aequitas is holding, which looks too thick 
and the knob at the lower end too large.
Also, when the groundline on the reverse is horizontal, 
Aequitas is leaning to the left at an angle of about 15 
degrees, which is not normal.

Compare the reverse to the contemporary reverse type
of Antoninus Pius coins (RIC 61 type):
http://www.wildwinds.com/coins/sear5/s4049.html