English translation of the 60+ German language pages of the enlightening and interesting work by Andreas Märkl, written in the copyright-free Vienna "Numismatische Zeitschrift" No. 16, Anno 1894. It explains and described the coins, mints and differentiating characteristics of the coinage of Claudius II and for anyone who has ever been frustrated by having to choose between the references of two seemingly identical coins, it is a MUST-READ. Why is the M of IMP sometimes written as IIII ? Was the mint described in RIC as "Gaul" probably Tarraco in Spain ? Why are there dots beneath the busts of some coins ?. The article includes a list showing all the possible characteristics of an example coin, AEQVITAS AVG which was struck with a seemingly identical reverse by every one of Claudius II's mints. A couple of sample coins pictures have been added.