Phalarae

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While most phalera seem to be circular and displayed on a 3 by 3 grid of straps this doesn’t seem to be a hard fast rule and variations in shape of the individual phalera are possible.

RRC 412/1 control mark pair 68 BM Specimen

I”m inclined to see the reverse symbol as a single phalera. and obverse as a dona militia, a display of phalerae