Collection. The core G-D-A-E remains—these are the main notes of the sustained harmony. The previous block (Block 2) extended it one fifth clockwise, filling in E-B melodically. This block extends it one fifth counterclockwise, filling in C-G melodically. The pitch collection in Block 3 is more closely affiliated with D natural minor than the D major or D melodic minor of the previous block (B and C♯ are replaced by B♭ and C).