piano scale
F natural minor
F1G2A♭♭3B♭4C5D♭♭6E♭♭7
The major scale started from its sixth degree: same seven notes, a different centre of gravity.
Written out
Every accidental is written in, rather than left to a key signature, so the letters can be read one at a time.
The step pattern
FWGHA♭WB♭WCHD♭WE♭WF
What is true of it
F natural minor is F, G, A♭, B♭, C, D♭ and E♭, and back to F.
Its steps are W – H – W – W – H – W – W, where W is a whole step and H a half.
On the same tonic, F harmonic minor differs from it by exactly one note.
Chords made only of these notes
Found by testing every chord in the catalogue against these 7 sounds, not chosen.