Diocletian. AD 284-305. Æ Sestertius (23mm, 5.40 g, 2h). Rome mint. Struck circa 285. IMP DIOCLETIANVS AVG, laureate and draped bust right / IOVI CONSER VAT AVGG, Jupiter standing facing, head left, holding thunderbolt and scepter. RIC V 202 var. (rev. legend; there described as a semis); Triton X, lot 752 (hammer $1700). Dark brown surfaces, rough and porous, deposits. Near VF. Very rare.
With his monetary reform in AD 274-275, Aurelian re-introduced the fully bronze denominations to the Roman trimetallic currency system. Two denominations were struck, a smaller piece of about 25 mm, about the same size and weight of the second century copper as, and a larger and heavier piece bearing a radiate portrait of the emperor, paired with a bust of his wife on a crescent. Although often catalogued as bronze asses and dupondii respectively, given the high inflation of the period, it is more now generally accepted they represent sesterii and double-sestertii. These bronzes would continue to be struck on and off for the next decade, with the latest appearing in the reign of Diocletian, around AD 285.