It is also prevalent in 20th century compositions by Alberto Ginastera, Almeida Prado, Béla Bartók, Milton Babbitt, and Arnold Schoenberg, by saxophonists John Coltrane and Oliver Nelson in the late 1950s and early 1960s, and bandleader Michael Brecker. Alternating E major and C minor triads form the augmented scale in the opening bars of the Finale in Shostakovich's Second Piano Trio. Prometheus scale The Prometheus scale is so called because of its prominent use in Alexander Scriabin's symphonic poem Prometheus: The Poem of Fire. Scriabin himself called this set of pitches, voiced as the simultaneity (in ascending order) C F B E A D the "mystic chord". Others have referred to it as the "Promethean chord". It may be thought of as C Lydian b7 without the 5th degree. Blues scale The blues scale is so named for its use of blue notes. Since blue notes are alternate inflections, strictly speaking there can be no one blues scale, but the scale most commonly called "the blues scale" comprises the minor pentatonic scale and an additional flat 5th scale degree: C E F G G B C. Tritone scale The tritone scale, C D E G G() B, is enharmonically equivalent to the Petrushka chord; it means a C major chord ( C E G() ) + G major chord's 2nd inversion ( D G B ). The two-semitone tritone scale, C D D F G A, is a symmetric scale consisting of a repeated pattern of two semitones followed by a major third now used for improvisation and may substitute for any mode of the jazz minor scale. The scale originated in Nicolas Slonimsky's book Thesaurus of Scales and Melodic Patterns through the "equal division of one octave into two parts," creating a tritone, and the "interpolation of two notes," adding two consequent semitones after the two resulting notes. The scale is the fifth mode of Messiaen's list. See also Hexachord Istrian scale References External links A model for hexatonic scales in 96-EDO, 96edo.com. Detailed Examination of Hexatonic Scales Originating in the Natural Scale/Harmonic Series The origin of triads and musica ficta filling in hexatonic gaps in the diatonic scale Tritones Musical scales lv:Blūza skaņkārta