This is an authentic original coin. Obv: Bust radiated, draped and with cuirass to the right, around legend: IMP CLAVDIVS AVG. Rev: Pax standing to the left carrying branch and scepter, around legend: PAX AVGVS.
This is most likely either a very rare or unique coin, because there is no such legend of the reverse in the catalogs. It may not be described anywhere or attributed like imitation. However, the precision of manufacture, weight, size and style do not allow this coin to be attributed to imitations. The coin has passed all the necessary conservation procedures.
I ask you to also look at the rest of the coins. Basically, these are rare or scarce coins, trial coins, coins, rare coins with stamp errors, etc.