This coin has the typical trapezoidal cross-section of an Egyptian bronze coin - apparently, the blanks were cast into this shape prior to being struck. At 32mm, this one is likely to be the denomination Sear calls a "hemidrachm" but Wildwinds calls a "drachm" (nomenclature for Romano-Egyptian coinage is still uncertain).
I've finally managed to track down the ID of this one: the figure on the reverse is identified as Isis Euploia (the Egyptian goddess Isis, in her role as protector of the voyages of ships) standing holding ears of grain and a ship's rudder; to the left is a ship under sail; to the right is the prow of another ship; below the two ships recline a female figure and a male figure (the male figure represents the Nile River, while the female symbolizes the sea). This example on the Ashmolean Museum website
is dated Year 18 of Antoninus Pius, or 154-155 AD. It's listed in the millennium Sear catalogue as number 4454, though Sear identifies the central figure as Tyche rather than Isis.
Sear adds a comment that this coin is meant to symbolize the fact that Alexandria was both a major seaport and a major river port; it was the New Orleans of the ancient world.
CV in Sear is $110 in Fine. Even in this condition, it's still better than your average scratchtray find.
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