Diocletian, 284-305. Aureus (Gold, 20 mm, 5.48 g, 1 h), Cyzicus (?), 286-287. IMP C C VAL DIOCLETIANVS AVG Laureate, draped and cuirassed bust of Diocletian to right, seen from behind. Rev. IOVI CONSERVATORI / S C Jupiter standing front, head to left and with chlamys draped over his shoulders, holding Victory on globe in his right hand and long scepter in his left. Calicó 4489 (but questioning its existence). Cohen 254 var. (with a star after the S C). RIC 296. Of the highest rarity, with Calicó being unable to confirm its existence. An exceptional piece, lustrous and very sharply struck from crisp and fresh dies. Virtually as struck.
This wonderful coin was struck after an early monetary reform by Diocletian that unified and raised the weight of Roman aurei to 1/60 of a pound or 5.46 g. It was struck in an uncertain eastern mint, perhaps Cyzicus, and praises Jupiter in his role as a preserver - an early precursor of Diocletian's extensive worship of the father of the gods as his personal comes later in his reign.