Watch List notes:

ROMAN & BYZANTINE COINS

Marcus Aurelius, 161-180. Semis or medalet (Orichalcum, 20mm, 6.33 g 12), Rome, 171, first semester. IMP M ANTONINVS AVG TR P XXV Laureate head of Marcus Aurelius to right. Rev. COS III Salus seated left on throne, holding scepter with her left hand and, with her right, holding patera from which she feeds a serpent coiled around an altar to her left. BMC -. Cohen -. RIC -. Apparently unpublished save for its auction appearances and probably unique. A lovely, well struck piece on a broad flan with a splendid olive green patina. Some very minor flaws and a slight edge split, otherwise, extremely fine.

From the Escalade Collection, Switzerland, ex Numismatica Genevensis 7, 27 November 2012, 370, from the collection of Martin Armstrong, Classical Numismatic Group E Sale 271, 11 January 2012, 82 and ex Numismatica Ars Classica 15, 18 May 1999, 376.
The exceptional character of this coin has not previously been emphasized. Small aes denominations ceased to be issued by the Rome mint after early in the reign of Antoninus Pius; so the appearance of one for Marcus Aurelius, especially one without S C on the reverse is very surprising. This very well struck, thick and large piece must have been produced as a form of donative, but for what event is uncertain. In any case the lack of S C aligns it clearly with the long series of larger medallions that were issued during the second half of the 2nd century.