The Tetrachalkon denomination
The tetrachalkon is an ancient Greek bronze denomination worth 4 chalkoi.

It is roughly equivalent to one hemiobol - or 1/12th of a drachm.
Tetrachalkon

(1) Apameia 133-48 BC
Obverse: laureate head of Zeus right
Reverse: Artemis Anatis facing AΠAME / HPAKΛEI / EΓΛO
Ref: BMC Phrygia 69; SNG Cop 183; SGCV I...
(2) Berenike II 46-221 BC
Obverse: BEΡENIKHΣ BAΣIΛIΣΣHΣ or abbreviated, head of Berenike II right, hair in a bun.
Reverse: BAΣIΛEΩΣ ΠTOΛEMAIOY, eagle standing left on thunderbolt, wings closed.
Ref: Svoronos 1055; BMC 17; Sear Greece ...
(3) Olympia 170-130 BC
Obverse: laureate head of Zeus right
Reverse: legend within wreath; FA / ΛEI / ΩN
Ref: Cf. BCD Olympia 302-5; cf. SNG Cope...
(4) Rhodos 229-205 BC
Obverse: Laureate head of Zeus right
Reverse: P - O, Rose with bud to right. Control: TE to left
Ref: Ashton 234; HGC 6, 1469.