Offered Numerian antoninianus belongs to the so-called type XXI or KA (Greek spelling for the numeral 21, where K stands for 20, A = 1) introduced in 274 as part of the Aurelian reform, which guaranteed that 20 units of copper contained 1 unit of silver, which was 5% of gold. Noteworthy is the mint mark on the reverse, where apart from the coin quality mark, there is also information about the sixth outbuilding of the mint.
Roman Imperial
Numerian (283-284), Billon antoninianus 282-283, Ticinum mint
Obverse: radiate, draped bust right
M AVR NVMERIANVS NOB C
Reverse: Numerian standing left in military dress, holding baton and scepter, PXXI in exerque
PRINCIPI IVVENTVT
Diameter 22 mm, weight 3.67 g
