Radiatus is a transitional denomination between antoninians and follises, minted during the tetrarchy in the eastern part of the Roman empire. Severus II radiatus are the rarest of all those minted.
There was only one listing of this coin from 2000 on Coinarchives in the last 20 years, where it was then sold for 120 DM.
Roman Imperial
Severus II as Caesar (305-306), Radiatus 305-306, Alexandria mint
Obverse: radiate head right
IMP C SEVERVS P F AVG
Reverse: Emperor standing right, receiving Victory on globe from Jupiter, standing left, holding sceptre, beetwen them letter Γ, ALE in exerque
CONCORDIA MILITVM
Weight 2,95 g.