The end of the
rev. legend is somewhat unclear in the photo; I was wondering whether it might be
COS II P P, which would be a new
legend form for
sestertii, and an additional
hybrid element, since P P also appears in the
obv. legend!
But no, it's just
COS II on the
rev., as shown by a coin in my
collection from the same
rev. die, on which the
legend is clearly [P M] TR.P - O - T.COS.II
S - C. The missing P M on my coin is nicely confirmed by your new acquisition. My coin is not a
mule, however; it has the correct long
obv. legend, with HADR AN - TONINVS, and bare-headed
portrait right.
Your
mule is indeed in
Strack, as
Okidoki suggested it might be: p. 321, no. 27, specimens in Naples, Bologna, and
Vatican. Unfortunately
Strack omits to tell us whether any of those specimens also have the
aegis like yours, since he uses the same code letter for
bust with fold of cloak or
aegis on shoulder as for plain
head without drapery or
aegis.
A
sestertius and a
dupondius in my
collection are similar
mules to yours, combining the new shortened
obv. legend of 139 with the old long
rev. legend, but here with
Pax standing
rev. type, and no
aegis on
obverse. The opposite kind of
mules, combining the old long
obv. legend with the shortened
rev. legend TR POT COS II S C, also occur:
Strack 755-6 and 759 reports two such
sestertii with the
Fides standing
type and one with
Annona standing, plus two such
dupondii with the
Fides type and three with the
Pax standing
type.
Sestertii of Pius with
aegis on shoulder are certainly exceptional! None are recorded in this
ANTONINVS AVG PIVS P P issue of 139 by
BMC or in my handwritten
additions to my copy thereof. Again we have to regret that Strack's
bust code system doesn't reveal whether or not he saw any such
sestertii.