"Harmonique" is a Coltrane original recorded in November 1959 for the album Coltrane Jazz, featuring Wynton Kelly on piano, Paul Chambers on bass, and Jimmy Cobb on drums. Set as a 12-bar blues in B-flat at a medium swing tempo of approximately 131 BPM, the performance derives its title from Coltrane's innovative use of harmonics and multiphonics on the tenor saxophone. Over three choruses, Coltrane experiments with overtone techniques that produce ghostly, flute-like tones above his normal register, a striking departure from conventional saxophone timbre that would influence generations of reed players. Kelly follows with two grounded choruses that bring the performance back to earth with his trademark bluesy elegance. The track stands as one of the most forward-looking pieces on Coltrane Jazz, demonstrating the saxophonist's tireless pursuit of new sonic possibilities. While the blues form provides a familiar structural anchor, Coltrane's timbral explorations push the music into uncharted territory. The rhythm section responds to these experiments with sensitivity, adjusting their dynamic approach to complement the unusual textures. Harmonique offers a glimpse of the radical experimentation that would increasingly characterize Coltrane's work throughout the 1960s.