Since the Iron Curtain came down it has become clear that huge numbers of Severan imitations were produced in the Balkans. However, there are few scholarly articles on these.

Imitations from this period are common. Here they are grouped by ruler in chronological order. One of each is illustrated here. The linked pages illustrate and discuss these and additional pieces.

Pieces tend to belong to one of these categories:
1)  Solid-silver imitations with unofficial style
        [These are rare. Why were they produced? The solid silver eliminates the profit motive.]
2)  Plated-silver imitations, struck, and with unofficial style
        [Struck for profit, these are very common.]
3)  Cast imitations (in official style) but with no plating. They appear to be copper or other base metal.
        [Did these ever have surface-silvering? Many do not look like it, but some have some thin light-metal surface. Casts cannot be created with the same silver-foil method used for fourrées. So, if they did have surface silvering, was it more like that of the later antoniniani?  Perhaps the counterfeiters perfected a process used later to make the surface-silvered antoninini of emperors (for example, Probus and Aurelian)  in later third century. Many extant ants show no traces of silver, but all(?) were originally surface-silvered.]
4)  Gray/black base-metal imitations
        [Good (official?) style, very dull gray or black metal, apparently not copper. Probably cast from official coins. But how did they get the silvering required to make them deceptive? Or, did they serve as currency even without being deceptive?]

 

A page of imitations of Septimius Severus (193-211) 

A page of imitations of Julia Domna, wife of Septimius Severus 

A page of imitations of Geta (AD 198-209-212)

A page of imitations of Caracalla (AD 196-217) and his wife, Plautilla    

  This piece: Diadumenian
A page of imitations of Macrinus (AD 217-218) and his son Diadumenian   

A page of imitations of Elagabalus (AD 218-222) and his family (here, his grandmother, Julia Maesa)   

A page of imitations of Severus Alexander (AD 222-235) and his Mother, Julia Mamaea

A page of imitations of Maximinus I (AD 235-238)

A page of imitations of Gordian III (AD 238-244)

  This piece: Philip I
A page of imitations of Philip I (AD 244-249), his wife Otacilia Severa, and their son Philip II

  This piece: Trajan Decius
A page of imitations of Trajan Decius (AD 249-251) and Trebonianus Gallus (AD 251-253)
 

This completes the list of fourrés through Trebonianus Gallus in 253.

An imitation of Gallienus:

Gallienus imitations are relatively scarce. Some are found as a very small percentage of the coins in large hoards of Gallo-Roman coins that include groups of "barbarous radiates" of Postumus and especially Tetricus I and II.  This site does not have a page on "barbarous radiates" (not for lack of interest, but for lack of the writer's time). I exhibit just this one unusual Gallienus imitation.
    IMP GALLIENVS AVG, radiate head right. Well done, but a little crude.
    /PAX AVG, Pax standing left holding up flower in right and with transvers sceptre in left, V in field left, star in field right.
    A thick AE17-15, 4.09 grams, 6:00.
    The small diameter and remarkably thick flan make this stand out as irregular in hand. On the screen the style is not bad. It is not far from official style, but I judge that it is on the imitation side of the fine line between official and irregular.