U+1D0C1 "𝃁" Byzantine Musical Symbol Fthora Diatoniki Ni Kato Unicode Character

U+1D0C1 "𝃁" Byzantine Musical Symbol Fthora Diatoniki Ni Kato is a specialized glyph used in Byzantine musical notation, a system developed for the chanting of liturgical texts in Eastern Orthodox and Byzantine Rite traditions. This symbol specifically represents a fthora, or modulation marker, indicating a shift to the diatonic genus (a specific set of intervals) for the note "Ni" in the lower octave. It functions as a critical instruction for the cantor, signaling a temporary alteration in the melodic scale's pitch structure to ensure the correct performance of the mode during a hymn or chant.