A transitional type of Athens tetradrachm. Called heterogeneous style due to the disparity of features within the style.
From after the arrival of Antigonus Gonatas, J. H. Kroll felt Athens did not issue official coinage until the second century B.C. Considering the inconsistency of the features, that the silver did not come from the Laurion mines and that they seem to have been struck over a short period and only in relatively small quantities, the heterogeneous style types discussed here were previously identified by Nicolet-Pierre and Kroll as unofficial coinage struck in Northern Greece. The Laurion mines are believed to have ceased operating early in the third century B.C., so later issues would not be struck from Laurion silver. Christophe Flament believes these heterogeneous types were struck at Athens and he has identified a series of six groups within the style. The groups can be distinguished by the following features:
Group A - The owl has a much broader head and the bill is much less schematic than the on the quadridigité style.
Group B - The owl has the same broad head as group A. The olive leaves are closer to parallel forming a smaller than usual angle. The spiral is the largest predominant element of the floral ornament on Athena 's helmet.
Group C - The reverse die was often a cylinder rather than the usual square and the die axis is usually from 9 - 12 (8 is usual for heterogeneous style). The floral ornament on the helmet includes a spiral but it is smaller.
Group D - The feathers on the owls body just above the legs form a rectangle with the appearance of a skirt.
Group E - This type is struck with better silver. The owl is similar to that on coins of the 4th century.
Group F - The floral ornament ends in four branches but not similar to fingers on a hand format of the quadridigité style. Athena 's hair is formed of larger pellets.
Flament, C. Le monnayage en argent d 'Athènes. De l 'époque archaïque à l 'époque hellénistique (c. 550-c. 40 av. J.-C.). (Lovain-la-Neuve, 2007).