Watch List notes:

Maximianus, first reign, 286-305. Argenteus (Silver, 18 mm, 3.39 g, 12 h), Rome, c. 300. MAXIMIA-NVS AVG Laureate head of Maximianus to right. Rev. XC /. / VI within laurel wreath. RIC 15b (Carthage). Very rare. Toned. Some remaining deposits, very minor scratches, scuff on the reverse, and with the reverse wreath struck partially flat, otherwise, about extremely fine.
The RIC attributed this issue to Carthage, but a hitherto unpublished example with the mintmark PR, and with very close stylistic parallels to this issue, was found in an English excavation, making the attribution to Rome more likely.