Nikopolis ad Istrum in Moesia Inferior, 193-217 AD., Julia Domna, Tetrassarion, Pick 1459, countermarked.

Nikopolis ad Istrum in Moesia Inferior, Julia Domna, 193-217 AD.,
Æ Tetrassarion (26-28 mm / 11,12 g), countermarked on both sides,
Obv.: IOYΛIA - [ΔOMNA CЄB] , her draped bust right; countermark Δ shaped incuse punch on neck and shoulder, 7 x 6 mm, Howgego 782 (3 pcs.).
Rev.: [VP AVP ΓAΛΛO]V NIKOΠOΛI ΠPOC I , river-god Istrosos reclining left, head right, holding reed with right and leaning with left arm on urn from wich water flows; countermark NIKO, incuse, 14 x 5 mm, Howgego 553 (3 pcs, 2 of which on reverses).
Pick (AMNG I), 1, 1459 ; BMC 3, 44, 20 ; Sear GIC 2314 ; for countermarks Howgego 782 and 553.
All coins that have the Δ countermark apparently also bear the NIKO countermark, so they must have been applied at the same time.