Minor Blues Scale

The Minor Blues scale is a scale derived from the Natural Minor Scale, but with an added "blue" note between the 4th and 5th scale degrees , and the removal of the 2nd and 6th scale degrees

Deriving the Minor Blues Scale
The standard Natural Minor Scale is based on the interval steps of W-W-H-W-W-H-W (where W is a whole step and H is a half step). The added flat V is known as the "Blue" note and is common in Jazz and Blues music. It is an out of scale note that adds a melancholic feel to the progression of the scale.

Minor Blues in C
To steps for the minor blues scale in C are: