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Akragas, Sicily, AE cast tetras, (4.32g) early 5th century BC,
tooth-shaped cast bronze, perhaps a weight, 

Eagle's head left.
Crab's claw. 

Sometimes referred to as the first bronze coin, this issue may
have been used as a weight, not a coin. Soon afterwards, bronze
coinage displaced the use of tiny silver fractions.

Hoover 130: Westermark 1979, 4