ISLANDS off ATTICA, Aegina. Circa 456/45-431 BC. Stater (Silver, 20mm, 12.30 g). Land tortoise with segmented shell; atop, countermark of human hand, with Σ to left; all within an oval indent. Rev. Incuse square with a skew pattern. Milbank pl. 2, 12. SNG Copenhagen 516. SNG Delepierre 1836. Toned. Obverse struck from a slightly corroded die and slightly off center, otherwise, good very fine.
Aegina Staters were commonly countermarked, but this particular countermark of an open hand is quite exceptional - the letter must stand for a particular individual or authority behind the issuance of this mark.