If you can list the
weight and size it would
help. Your coin is a die match for a known
fake,
hendin F655a.2, which is listed in
his book not kosker. However, that being said, many
cast fakes of shekels are from known real shekels, so a die match of a known
fake doesn't totally rule out a legitimate coin. Just from the photo I can't say the coin is real or not. If the
weight is low that would be a bad sign. To me the coin doesn't quite look right, but from the photo I can't be more specific.
Ronn