The Triassarion denomination
The triassarion was a bronze denomination worth 3 asses - assarion in Greek.

It was commonly struck by Roman Provincial mints, and was not struck to a standard weight but rather to some local standard. It was simply a coin worth 3 of the local basic coin denomination.
Triassarion

(1) Tranquillina 241-244 AD
Obverse: CABINIA TPANKVLINA Draped bust right, wearing stephane.
Reverse: ICTPIHNON Sea-eagle left, grasping dolphin with talons.
Ref: Moushmov 200, AMNG I 529, Varbanov ...
(2) Valerian I 253-254 AD
Obverse: radiate, draped and cuirassed bust right AVT K OVAΛEPIANOC CE
Reverse: Tyche standing left, agnostic crown in both hands; ANAZAPBOV EN_ΔOX M(HT) ET BOC / T/Γ/Γ _ A/K/M
Ref: SNG Levante 1521, Zeigler 806, BMC ...