Here is a coin with a PROVIDENTIAE reverse... and it is not a campgate. This coin has seen better days, but it is a rare type that marks the occasion of the transfer of the Ostia mint to Arles in A.D. 313. There was another type also issued at the same time to mark this event- VTILITAS PVBLICA (second pic below). The VTILITAS reverse depicts the mint leaving Ostia, as the prow is pointed away from the soldier, so it is departing; while the PROVIDENTIAE type depicts the mint arriving at Arles, since personification of Arles is greeting it and the prow shows that it is arriving. The figure on the prow is described as Utilitas with the attributes of Moneta, but perhaps she is just Moneta with her usual attributes- scales and cornucopia.
Constantine I
A.D. 313- 315
2.4gm
IMP CONSTANTINVS PF AVG; bust left, laureate and cuirassed, spear across right shoulder, shield across left.
PROVIDENTIAE AVGG; Moneta standing on prow, holding cornucopiae, received by turreted Arles holding standard (RIC calls it a scepter).
In ex. QARL
RIC VII Arles 30