Notes: C, D, E, F, G, Ab, and Bb - Key: C - Category: Octatonic Scales
The C Major-Minor uses eight notes per octave. Because of this same reason it is a member of the so called Octatonic -scales that have Eight-note (or Eight-tone). On the piano keyboard, it is made up of two black keys: Ab, and Bb and five white keys: C, D, E, F, and G. This combination makes this scale - as well as the C Prometheus, C Prometheus Liszt, and C Prometheus Neapolitan - as great choices for composing or improvising music.
If we take a look a the key signature of the C Major-Minor Scale we can find it has two flats and no sharps. Therefore, on sheet music you will find two accidentals on the score. The notes of this scale are: C, D, E, F, G, Ab, and Bb.