I don't have an obverse picture for this coin, but it is either Constantius II or Gallus, so Aquileia 195 or 196. RIC rates this type as common, but I believe that they are not actually that common. This might be an example of major collections having these because the Chi-Rho makes it more collectible, which does not really reflect how often they really show up. Wildwinds has two examples for Gallus, but none for Constantius II.
The number LXXII on this coin likely stands for 1/72 roman pounds