Only a handful of “fine work” pieces were actually made. This fact alone should have alerted the decision makers that hammered techniques, although capable of making good quality specimens could only achieve this in very limited numbers under strictly controlled conditions. Pierre Blondeau on the other hand produced around 100 identical sample pieces in a test run.
The obverse and reverse dies once used, were placed into regular production so there are pieces existing which use either the obverse or reverse die only. These are not “fine work” specimens - see below for an example where the reverse die in use appears to be the “fine work” die.