Herod I minted a lot of (real) leptons, so if there's a historical basis to the story and Mark isn't just emphasising the woman's poverty, then most likely she'd have had Herod's coins.
Jannaeus did mint a few (real) lepta, but they're rare and expensive; the most you can say about these is that a few of the crudest issues were down to lepton size. My heaviest example weighs 4.08g, and I absolutely refuse to believe a heffalump like that could be a lepton, when most of them are under 1g!
The
weights vary for even regular prutot. A regular prutah's
weight can span about 6 grams, as pointed out in
AJC. Could these coins, in
antiquity, be weighed for value, and not just assume it is a
prutah value?
This seems logical, because otherwise, someone is always getting less then the value they payed/earned.
You write that you cannot accept the half-prutah value to these coins, because of an oversized coin you own. I could argue that, because there are regular
types of
Hasmonean coins more then the
prutah weight of 1 gram, these coins are actually 2-prutot, just most are undersized at 1 gram. Some
Hasmonean coins can reach the size of 7 grams, a greater difference in
weight then the half
prutah you have.
My argument would be probably incorrect. Most of the prutot that we know to be prutot 100% weigh about 1 gram, so we conclude its value is a
prutah.
These coins usually weigh under 1 gram, so why can't we assume that these coins are half prutot, using the same logic?
-Aarmale
EDIT: Is the mark on the
reverse of the coin from 8:00-9:00 anything?