Since they are NOT marked as copies and do not have a obverse reverse orientation that would allow both sides to be 'up' when mounted, I am not sure I believe this claim. All of the above are struck on flans thinner than appropriate. All are struck with great force giving sharp detail but none really have proper fine detail in the hair. Most copy rather rare coins. The common Emperors are represented by rare varieties.
Portraits are all quite recognizable as their subjects but the styles are still just a bit off.
All are struck on flans of similar fabric in the same metal. This is rumored to be from melting down old European base silver coins. The first century copies are too base while the Pescennius Niger is much too fine. It is interesting that an attempt was made to duplicate the diameters of the coins with the Augustus being much wider than the later coins. These samples are starting to tone.