Watch List notes:

Diocletian (284-305), Argenteus, Siscia, c. AD 294-295; AR (g 2,64; mm 18; h 7); DIOCLETI - ANVS AVG, laureate head r., Rv. VIRTVS – MILITVM, eight-turreted camp gate in front of which the four tetrarchs swear over tripod. RIC 43a.
Rare, cabinet tone, high relief but slightly flan crack, anyway about fdc.