Antoninus Pius and Marcus Aurelius AE As. 140-144 AD. 

ANTONINVS AVG PIVS PP TR P COS III, laureate head right.
AVRELIVS CAESAR AVG PII F COS, SC below, bare-headed, draped
bust of Marcus Aurelius left. 

RIC 1224; Cohen 39. 

Note: the reverse appears to show the legend AVRELIVS CAESAR 
AVG PII F COS III but this is either an engraver's error, or
an engraver's error, or the lines are the lines of his 
shoulder and back.
No AE coins are known for Marcus Aurelius as Caesar as COS 
II and those from COS III show him as an older figure (161 
AD), 17 years after this coin was struck) and in addition, 
by that time Antoninus Pius was COS IIII. 
The seller adds: "It is also possible the reverse legend has 
been tooled to add the consular number"

With permission of Heritage World Coin Auctions, April 2013,
lot 25863, sold for $160.