Leo IV the Khazar, with Constantine VI, 775-780. Miliaresion (Silver, 21 mm, 2.06 g, 7 h), Constantinopolis, 776-780. ҺSЧS XRISTЧS ҺICA Cross potent on three steps; in fields to left and right, C - I engraved. Rev. LЄOҺ / S COҺST/AҺTIҺЄ Є / C ΘЄЧ ЬA/SILIS in five lines. DOC 3. SB 1585. Good very fine.
What the unusual letters C - I in the obverse fields stand for is unclear, but the engraving was certainly done with great care