A corroded archaic owl - countermark identification help needed

[robinjojo]

This a somewhat unusual archaic owl in that it has what appears to be a countermark on the obverse helmet.  I don't think it is corrosion, nor metal flaws, which are common with archaic owls, and can be seen elsewhere on the example.  The spoke design almost suggests a countermark applied in Aegina, since it seems to be a "skew" style design. 

I've seen many archaic owls with test cuts, but not too many countermarked.  Any thoughts?  Thanks

Athens, archaic owl, circa 480 BC.  Corroded and countermarked.

Seltman group Gi

16.26 grams

Here's the countermark:

[Spaniard]

Looks like corrosion to me?..similar depth to the spot on the cheek?

[robinjojo]

I'd agree, but the pattern is just too geometrical and pretty uniform to be corrosion.  The corrosion on this coin seems more or less even, with some areas not as affected as others.  The other pits could be flan (metal) defects, which are quite common with these coins.

[robinjojo]

Here is a rather similar countermark that was applied to an Aegina stater, a little rounder than the one on the OP coin.

[robinjojo]

Here's an Athenian archaic tetradrachm with metal flaw on the obverse.

Athens, archaic owl, circa 480 BC.

17.5 grams