I just got this example; which I thought was interesting because Diocletian (on the left) has curly hair and what looks like a beard, versus the normal laureate bust. The pateras are also overlapping.
Diocletian
A.D. 289- 290
Ӕ Antoninianus 23mm 3.9gm
IMP C C VAL DIOCLETIANVS P F AVG; radiate and cuirassed bust right.
CONSERVATOR AVGG; Diocletian stg. r., and Jupiter stg. l., sacrificing at altar, each holding sceptre.
In ex. XXIΓ•BI•
RIC V Siscia 263
here is a comparison with the normal type
https://constantinethegreatcoins.com/CONSERVATOR/